QUESTIONSHEET
1
(a) A base 1
B collector 1
C emitter 1
(b) 0.12 + 2.7 1
= 2.82 mA 1
(c) Zero or very low current 1
TOTAL / 6
QUESTIONSHEET
2
(a)
Thermistor in place 1
Thermistor symbol correct 1
Fixed resistor in place 1
(b) Fixed resistor replaced 1
by variable resistor 1
TOTAL / 5
QUESTIONSHEET
3
(a) One mark for each
|
A on/off |
B safety screen |
Drill on/off |
|
on |
on |
on |
|
on |
off |
off |
|
off |
on |
off |
|
off |
off |
off |
4
(b) (i) One mark per line
|
A |
B |
C |
|
1 |
1 |
1 |
|
1 |
0 |
0 |
|
0 |
1 |
0 |
|
0 |
0 |
0 |
4
(ii) AND gate 1
TOTAL / 9
QUESTIONSHEET
4
(a)
1
(b)
|
A |
B |
Output |
|
0 |
0 |
0 |
|
0 |
1 |
1 |
|
1 |
0 |
1 |
|
1 |
1 |
1 |
4
TOTAL / 5
QUESTIONSHEET
5
(a) (i) One 1
(ii) Input Output
1 0
0 1 2
(iii) Inverts/reverses the input 1
(b) (i) NOT and AND 1
(ii)
Correct symbols 1
NOT gate follows 1
AND gate 1
TOTAL / 8
QUESTIONSHEET
6
(a) One mark for each point:
Taking some of the output 1
and feeding it back 1
to the input 1
(b) Line drawn from output to input 1
(c) One mark for each point:
System can check how effective it is 1
and change its operation if necessary 1
This makes it more accurate/sentitive 1
TOTAL / 7
QUESTIONSHEET
7
(a) Bell stops ringing 1
(b) (i) Wire
connected between bell and relay 1
(ii) A switch 1
in series with bell 1
(c) It is stable in two states/ there are two states which the circuit will stay 1
It stays in one state unless reset 1
TOTAL / 6
QUESTIONSHEET
8
(a) Any Two From
seat belt connected
engine not running
no-one sitting in passenger seat 2 2
(b)
|
Input A |
Input B |
P (A and B) |
Q (Not B) |
alarm |
|
0 |
0 |
0 |
1 |
0 |
|
0 |
1 |
0 |
0 |
0 |
|
1 |
0 |
0 |
1 |
1 |
|
1 |
1 |
1 |
0 |
0 |
5 5
(one mark for each correctly completed column)
TOTAL / 7
QUESTIONSHEET
9
(a) (i) Nothing/Zero 1
(ii) The diode only lets current flow 1
in one direction 1
(b) Only current in positive (or negative) direction flows 1
Half of sine wave cut out 1
Current only flows
for half the time/ cycle 1
t
1
TOTAL / 7
QUESTIONSHEET
10
(a) Input voltage / V divided up 1
by ratio of size of resistors 1
(b) (i) Variable resistor/ R2 1
(ii) Collector current high/ current now flows through collector 1
(iii) Lamp comes on 1
TOTAL / 5
QUESTIONSHEET
11
(a) One mark for each point:
Resistance goes up 1
Voltage across transistor increases 1
Transistor switches on 1
Lamp comes on 1
(b) Thermistor 1
TOTAL / 5
QUESTIONSHEET
12
(a) LDR 1
Pressure 1
(b) NOT 1
AND 1
porch light light sensor
(c)
pressure sensor
Light sensors connected to NOT gate 1
Pressure sensor forms one input to AND gate 1
Output from NOT gate forms second input 1
Output from AND gate connected to porch light 1
TOTAL / 8
QUESTIONSHEET
13
(a)
(b) (i) System cannot monitor the water temperature 1
The central heating system could get hotter indefinitely/
the home would overheat 1
(ii) Boiler temperature sensor loop 1
Feedback loop 1
Line drawn from boiler temperature sensor to the processor 1
2
TOTAL / 7
QUESTIONSHEET
14
(a) Thermistor 1
Switch for alarm 1
(b) AND 1
(c) Buzzer/ bell/ LED/ lamp 1
(d) Replace alarm 1
By relay switch 1
Connect to heater 1
TOTAL / 7
QUESTIONSHEET
15
(a) (i) falls/gets lower 1 1
(ii) increases/gets higher 1 1
(iii) replace lamp with buzzer/bell 1 1
ensure room light plays on LDR 1 1
(b) (i) change sensitivity/adjust required light level for operation 1
(ii) light on LDR falls/gets less 1 1
resistance increases to exceed that of R2 1 1
current flows though lamp 1
TOTAL / 8
QUESTIONSHEET
16
(a) (i) circuit with two switches 1 1
in series 1 1
(ii) two inputs 1 1
passing through AND gate to machine 1 1
(iii) electronic components less likely to fail 1 1
lower current used 1 1
(b) thermistor 1 1
LDR 1 1
Buzzer or bell 1 1
TOTAL / 9
QUESTIONSHEET
17
PROCESSOR INPUT OUTPUT
(a)
3
(b) (i) Any one of:
mircophone, pressure switch, thermistor, light dependent resistor 1
(ii) Any one of:
loudspeaker, bell, buzzer, light emitting diode, lamp, motor 1
TOTAL / 5
QUESTIONSHEET
18
|
Name |
Symbol |
What is the output? |
|
|
|
Light |
|
|
|
Sound |
|
|
|
Movement |
4
TOTAL / 4
QUESTIONSHEET
19
(a) Light-emitting diode 1 1
(b) lower current used 1 1
less likely to fail 1 1
do not get hot 1 1
(c) (i) 7 1 1
(ii) 2
4 6
2
(iii) 8 shows when all LEDs are lit 1 1
rapid change makes all appear to be lit 1 1
TOTAL / 9
QUESTIONSHEET
20
(a) (i) light comes on/lamp lights 1 1
(ii) light/lamp goes out 1 1
(b) (i) use normally closed switch on door/door jam 1
magnet on door jam/door 1 1
when door opens switch closes and operates alarm 1
(ii) normally open switch on body/door 1 1
magnet on door/body 1 1
when door opens switch opens and turns off power 1
TOTAL / 8