High Demand Questions                            QUESTIONSHEET 1

 

 

(a) In the circuit below, lamps P and Q are identical. The reading on the ammeter is 3A. The cell shown is of emf. 6V.

 


         

 

           

 

 

 

 

 

 

 

 

 

     Calculate the current that passes through lamp P.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ..................................................................................................................................................................   

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 (b)If a voltmeter was connected across lamp P, what would it read ?

                                                                                                                                                                       

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

 (c)Calculate the resistance of lamp P.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 [3]

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                TOTAL                                                                                                                                                                    9

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 6  


High Demand Questions                            QUESTIONSHEET 2

 

 

(a) Resistors of 5 ohms and 10 ohms are connected in series with a battery supplying 3 volts.

     What is the total resistance ?

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 (b)Calculate the current which flows in the circuit.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 5


High Demand Questions                            QUESTIONSHEET 3

 

 

(a) Resistors of 2 ohms and 4 ohms are connected in parallel across a battery supplying 6 volts.

     Another resistor of 5 ohms is connected in series with the battery. Draw the circuit.

         

 

 

 

 

 

 

 

 

                                                                                                                                                                  [3]                          

 

 (b)Calculate the total resistance in the circuit.

                                                                                                                                                                                    (4)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [4]

  

(c) Calculate the current flowing through the 5 ohm resistor.

                                                                                                                                                                     

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TOTAL  / 9     


High Demand Questions                            QUESTIONSHEET 4

 

 

(a) A lamp is rated at 12 V, 6W.

     (i)    Explain what this means.                                                                                                                                            

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

  

     (ii)    How many joules of energy are transferred by the lamp in 5 minutes ?

                                                                                                                                                                       

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [4]

 

(b) (i)    Calculate the current passing through the lamp when it is connected to a 12 V supply.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

     (ii)    Calculate the resistance of the lamp in these circumstances.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(c) A 24 V supply is used to connect two such lamps in series.

     What difference will there be, if any, in the current and resistance of the lamp ?

                                                                                                                                                                     

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                TOTAL    / 12


High Demand Questions                            QUESTIONSHEET 5

 

 

In the circuit below, 0.6 A flows through the 10 ohm resistor.

 

    

 

 

 

 

 

 

 

 

 


 

 

(a) Calculate the current flowing through the 20 ohm resistor.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(b) Calculate the current flowing through the battery.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(c) Calculate the voltage supplied by the battery.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 7


High Demand Questions                            QUESTIONSHEET 6

 

 

Each of the resistors in the circuit below has a resistance of 10 W.

10 W

 
         

 

10 W

 
 

 

 


10 W

 
 

 

 

 

 

 

 


(a) Calculate the resistance of the two parallel resistors.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

  

(b) Calculate the total resistance in the circuit.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 (c)Calculate the current through each of the resistors.

                                                                                                                                                                     

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TOTAL  /  7

High Demand Questions                            QUESTIONSHEET 7

 

 

(a) Calculate the total resistance of resistors of 2 W, 5 W and 10 W when connected:

 

     (i)    in series with each other

                                                                                                                                                                       

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

  

      (ii)   in parallel with each other.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 (b)In which arrangement will the current in the circuit be larger? Explain your answer.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 8


High Demand Questions                            QUESTIONSHEET 8

 

 

Resistors of 3 W, 6 W, 6 W and 12 W are connected up as shown in the diagram.

12v

 
 


         

 

 

 

 

 

 

 

 

 

 


 

(a) Calculate the total resistance when both switches are closed.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [4]

 

 (b)Calculate the total current supplied when both switches are closed.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

  

(c) Calculate the current in the 3 W resistor when switch S1 is closed and switch S2 is open.

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

(d) Calculate the current supplied when both switches are open.

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                  TOTAL  / 11


Medium Demand Questions                       QUESTIONSHEET 9

 

 

(a) Electric current is measured in amps.

     Which of the following quantities is equal to one amp (1A)? Circle the correct answer

 

            A    one ohm per volt

            B    one volt per second

            C    one coulomb per second

            D    one joule per coulomb

            E     one coulomb per ohm

           

 

 (b)(i)    What is meant by an electric current ?

                                                                                                                                                                                    (3)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

      (ii)     State in which of the following circuits the lamp would light. There may be more than one correct answer.

         

         

 


         

A

 

C

 
 

 

 

 

 

 


             

                                                                                                                                                                 .................................................................................................................................................. [1]               .......................................................................................................................................................................    (1)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 5


Medium Demand Questions                      QUESTIONSHEET 10

 

The diagram shows a circuit with three identical lamps.

The ammeter, A1, shows a reading of 1.5 A.

 


         

 

1.5 A

 
  

 

 

 

 

 

 

 

 

 


(a) Indicate on the diagram where you would insert a switch so that it will switch on or off lamps L2

     and L3, but will not affect lamp L1.                                                                                                         [1]              

 

(b) What name is given to this arrangement of connecting lamps ?

                                                                                                                                                                                    (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

(c) What will be the reading on ammeter A2 ?

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

  

(d) What will be the reading on the voltmeter ?

                                                                                                                                                                                    (1)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 5


Medium Demand Questions                                      QUESTIONSHEET 11

 

(a) An ammeter of low resistance is used to measure the current flowing in a circuit.

     Explain why it must have a low resistance.

                                                                                                                                                                                     (2)

                                                                                                                                                                      ..................................................................................................................................................................   

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(b) (i)    How should a voltmeter be connected in a circuit ?

                                                                                                                                                                                    (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

   

     (ii)    Should a voltmeter have a high or low resistance ? Explain your answer.

                                                                                                                                                                     

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TOTAL  / 6


Medium Demand Questions                      QUESTIONSHEET 12

 

 

The potential difference and current for an electrical component is measured.

The results are shown in the table below.

 

Pd / V

0.5

1.0

2.0

3.0

4.0

5.0

6.0

7.0

I / A

.020

.040

0.56

0.75

0.88

0.93

1.00

1.08

 

(a)        Plot a graph of pd (y axis) against I (x axis)                                                                                     [4]

                                                                                                                                                                                                       (4)

 

 

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(b) (i)    Does the component obey Ohm’s law? ?

                                                                                                                                                                                         (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

    

     (ii)    Explain your answer.

                                                                                                                                                                                         (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

      (iii)  Suggest what the component could be.

    

                                                                                                                                                                 ............................................................................................................................................................ [1]                   

 

 

 

 

 

                                                                                                                                                    TOTAL  / 8


Medium Demand Questions                      QUESTIONSHEET 13

 

A student wishes to investigate whether a component obeys Ohm’s law.

 

(a) State Ohm’s law.

                                                                                                                                                                                         (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(b) Draw a suitable circuit that could be used for the investigation.                                                                       

         

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                                 [4]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 6

 

 

Medium Demand Questions                      QUESTIONSHEET 14

 

Below are shown graphs of I against V for three different components; a diode, a lamp filament

and a metal wire.

    

All were at constant temperature.

 

         

 


 

I

 

I

 
 

 

 

 

 

 

 

 

 


 

(a) Identify which graph belongs to which component.

                                                                                                                                                                     

     A ............................................................................................................................................................

 

     B ............................................................................................................................................................

 

     C ........................................................................................................................................................ [3]

 

 (b)(i)    Which graph shows an ohmic conductor ?

                                                                                                                                                                                    (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

     (ii)    Which graph shows a component in which resistance increases ?

                                                                                                                                                                                    (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 5


Medium Demand Questions                      QUESTIONSHEET 15

 

A machine in a workshop will only operate when the safety guard is in place.  There is a large switch

on the machine and a switch where it is plugged into the mains.

 

(a) (i)    Draw a circuit diagram showing the switches for the machine.

           

 

 

 

 

 

 

 

 

                                                                                                                                                                     

 

                                                                                                                                                                 [3]

     (ii)   Explain why the switches are placed in the circuit in the way in which you have drawn them.

                                                                                                                                                                                              (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(b) Two switches are used when you want to able to operate something from two different places. 

     (eg a light at each end of a corridor).

     Explain how the arrangement of the switches will differ from that in the machine.                                         

                                                                                                                                                                                              (3)

                                                                                                                                                                      ..................................................................................................................................................................   

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 8

 

 

Medium Demand Questions                      QUESTIONSHEET 16

 

A student is asked to investigate how the resistance of a wire varies with its length.

 

(a) Briefly describe how this could be done.

                                                                                                                                                                                    (4)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

     ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [4]

 

(b) Here are the results of the experiment.

 

Length of wire/cm

0.0

10

20

30

40

50

Resistance/ohms

0.0

4.5

9.1

13.6

18.1

22.3

 

   (i)      Plot a graph of length of wire against resistance.                                                                              [3]

                                                                                                                                                                                         (3)

 


  

 

 

 

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                (Continued...)

 

 

Medium Demand Questions           QUESTIONSHEET 16 CONTINUED

 

 

     (ii)    What can you conclude about how resistance of the wire varies with length?

                                                                                                                                                                                              (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

     (iii)     How is this made use of in a dimmer switch ?

                                                                                                                                                                                         (3)

     ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [3]

 

 

 

 

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                  TOTAL  / 12


Low Demand Questions                           QUESTIONSHEET 17

 

                                  

(a) Name each of the components shown.

 

         

 

 

 

 

 

 

 

 

 


C

 

D

 
                                                                                                                                                                 [4]

 

 

(b) What is the purpose of component D ?

                                                                                                                                                                     

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

 

 

 

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 5


Low Demand Questions                           QUESTIONSHEET 18

 


A torch battery represented by                 produces 1.5 volts.

 

(a)        Write down the voltage shown on the voltmeter in each of the following circuits.

    

 


     (i)

 

 

                                                                                                                                                                     

 

 

                                                                                                                                                                 ............................................................................................................................................................ [1]

+

 
 

     (ii)

 

 

 

 

 


                                                                                                                                                                 ............................................................................................................................................................ [1]

 


     (iii)

 

 

 

 

 


                                                                                                                                                                 ............................................................................................................................................................ [1]

+

 
 


     (iv)

 

 

 

 

 


                                                                                                                                                                 ............................................................................................................................................................ [1]

 

+

 
     (v)

 

 

 

 

 

 

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

(b)         Explain why you cannot light a car headlamp bulb with a 1.5 V battery.

                                                                                                                                                                                         (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

(c)        What happens to the size of a current in a circuit when the voltage increases?

                                                                                                                                                                                         (1)

                                                                                                                                                                 [1]

 

                                                                                                                                                    TOTAL  / 7  

Low Demand Questions                           QUESTIONSHEET 19

 

Here is a list some materials in order of their ability to conduct electricity.  The best conductor is

at the top and poorest one at the bottom.

 

            silver

            copper

            aluminium

            water

            PVC

            rubber

 

Copper is used in household wiring, but it is not the best conductor.

 

(a) Why is silver not used?

                                                                                                                                                                                         (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

(b) Aluminium is used in overhead power cables.

     Why is copper not used?

                                                                                                                                                                                         (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]

 

(c) Which two materials from the list are used to insulate electrical wires?

                                                                                                                                                                                         (2)

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(d) Explain why bathrooms are always fitted with pull-cord switches.

                                                                                                                                                                                         (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 6  


Low Demand Questions                           QUESTIONSHEET 20

 

Christmas tree lights are usually wired in series.  If one bulb stops working, the others do too.

 

(a) Explain what is meant by in series.

                                                                                                                                                                                    (2)

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(b) If there are 20 bulbs in a set of Christmas tree lights which operate from the mains (240 volts), what would be the voltage across each bulb?

                                                                                                                                                                                         (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(c) Why is it wrong to replace a bulb from a 20-bulb set of lights with one from a 40-bulb set?

                                                                                                                                                                                    (2)

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

(d) Why is it wrong to use

     (i)    a 3 amp fuse in the plug of an electric fire using 10 amps?

                                                                                                                                                                                         (1)

                                                                                                                                                                 ............................................................................................................................................................ [1]  

 

     (ii)    a 13 amp fuse in the plug of a radio using 1.5 amps?

                       

                                                                                                                                                                      ................................................................................................................................................................

 

                                                                                                                                                                 ............................................................................................................................................................ [2]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                                                                                                                    TOTAL  / 9