Question
The diagram shows a circuit containing a power supply, a lamp and a motor. Three ammeters measure the current at different points in the circuit. The readings on the ammeters are I1, I2 and I3.
Which statement about the ammeter readings is correct?
All three readings are the same.
11 is greater than I2 and is greater than I3.
I2 is greater than I1 and is greater than I3.
I3 is greater than I1 and is greater than I2.
Answer/Explanation
Ans: B
Question
A student designs a circuit to use as a dimmer switch for a lamp.
What happens to the brightness of the lamp and the potential difference (p.d.) across the lamp, when the slider is moved from X to Y?
| brightness of lamp | p.d. across the lamp |
A | decreases | decreases |
B | decreases | increases |
C | increases | decreases |
D | increases | increases |
Answer/Explanation
Ans: A
Question
Which electrical component is connected in series with an electric circuit to protect it from damage by a very large current?
earth wire
fuse
relay
thermistor
Answer/Explanation
Ans: B
Question
The circuit diagram shows a cell connected to an ammeter and two resistors.
What is the current in the circuit?
A 0.75 A B 1.3 A C 12 A D 48 A
Answer/Explanation
Ans: A
Question
The diagram shows an electrical circuit.
Which row describes what happens when the temperature rises?
| resistance of component X | potential difference (p.d.) across component Y |
A | decreases | decreases |
B | decreases | increases |
C | increases | decreases |
D | increases | increases |
Answer/Explanation
Ans: B
Question
A student sets up a circuit containing a battery of two cells and three lamps, as shown.
What is the circuit diagram for this arrangement?
A B C D
Answer/Explanation
Ans: A