Physics for IGCSE & O level - Electricity (Section 5)
1
What is the relationship between current and the number of parallel paths in a circuit?
Одговорити
(B)
As the number of paths increases, the current increases
2
Which component is typically used to change the voltage of an AC supply?
Одговорити
(C)
Transformer
3
What is a reed switch activated by?
Одговорити
(C)
A magnet
4
Which of the following are correct about an appliance's power rating?
Одговорити
A
B
C
5
What do charges do in a Van de Graaff generator?
Одговорити
(B)
They become concentrated on the surface of a sphere
6
What are the components that constitute the basic circuit rules?
Одговорити
A
B
C
7
What is the formula for calculating the total resistance of resistors in parallel?
Одговорити
(B)
1/R_total = 1/R1 + 1/R2
8
Which of the following is a common example of a parallel circuit application?
Одговорити
(C)
Household electrical wiring
9
In a series circuit, if one resistor has a voltage drop of 5V, and another has a voltage drop of 10V, what is the total voltage drop across both resistors?
Одговорити
(C)
15V
10
Which statement best describes the role of a battery in a circuit?
Одговорити
(C)
It provides the voltage (potential difference).
11
Which of the following describes a 'short circuit'?
Одговорити
(B)
Low resistance and high current
12
What is the effect on the current in a circuit if the resistance is doubled while the voltage remains constant?
Одговорити
(B)
Current halves
13
What is the frequency of the alternating current (AC) supply in most of Europe?
Одговорити
(A)
50 Hz
14
What is the role of a live wire in a domestic electrical supply?
Одговорити
(B)
It carries current to the appliance
15
What does the symbol 'Ω' represent in electrical circuits?
Одговорити
(C)
Resistance
16
In a series circuit, if one component breaks, what happens to the rest of the circuit?
Одговорити
(B)
The circuit stops working.
17
In a series circuit, if one component fails (breaks the circuit), what happens to the rest of the components?
Одговорити
(B)
They also fail.
18
What is the unit of power?
Одговорити
(C)
Watt
19
Which of the following are components of a simple circuit?
Одговорити
A
B
C
D
20
If a lightbulb uses 100J of energy every second, what is its power?
Одговорити
(A)
100 Watts
21
Which of the following is a symbol for a resistor?
Одговорити
(D)
-///-
22
What are the parts of an atom?
Одговорити
A
B
C
23
Which of the following is a source of AC electricity?
Одговорити
(C)
A mains socket
24
In a circuit with a voltage source, a resistor, and a light bulb in series. If the resistance of the resistor increases, what happens to the brightness of the light bulb?
Одговорити
(B)
The bulb will get dimmer.
25
How is resistance affected by material type?
Одговорити
(C)
Different materials have varying resistance.
26
What is the standard voltage rating for a 3-pin plug in the UK?
Одговорити
(C)
230V
27
Which of the following best describes the function of a variable resistor (rheostat)?
Одговорити
(C)
To change the resistance in a circuit.
28
What happens to the overall resistance of a circuit if components are added in series?
Одговорити
(B)
It increases
29
What is the purpose of the fuse in an electrical circuit?
Одговорити
(C)
To break the circuit if the current exceeds a safe level.
30
What is the term for the opposition to the flow of electric current?
Одговорити
(B)
Resistance
31
Which component opposes the flow of current in a circuit?
Одговорити
(B)
Resistor
32
What is the unit used to measure resistance?
Одговорити
(D)
Ohm
33
What is the effect of increasing the voltage in a circuit, assuming the resistance stays the same?
Одговорити
(C)
The current increases
34
What component is used to block DC current and allow AC current to pass?
Одговорити
(C)
Diode
35
In a parallel circuit, what is the same across all components?
Одговорити
(A)
Voltage
36
Which of the following appliances is most likely to have a three-pin plug?
Одговорити
(C)
A washing machine
37
If you plug a 1000W appliance into a 230V socket, how much current does it draw?
Одговорити
(A)
4.35 A
38
What is a function of a fuse?
Одговорити
(B)
To limit the current flow.
39
Which quantity is measured in Amperes (A)?
Одговорити
(B)
Current
40
Which of the following is a unit of electrical power?
Одговорити
(C)
Watt
41
What happens to the current in a series circuit if the voltage is increased and the resistance remains the same?
Одговорити
(A)
The current increases
42
What are the units of voltage?
Одговорити
(B)
Volts
43
What is the main purpose of an earth wire in an electrical appliance?
Одговорити
(B)
To provide a path for fault current to flow to earth.
44
What is the effect of a double-insulated appliance regarding earthing?
Одговорити
(B)
It does not require an earth wire.
45
What would be the consequence of a fuse having too high a current rating?
Одговорити
(C)
The appliance could overheat and cause a fire.
46
Which of the following is a non-ohmic device?
Одговорити
(C)
A diode
47
Which of the following factors does NOT affect the resistance of a wire?
Одговорити
(D)
Weight
48
What is a key component in a simple circuit?
Одговорити
(B)
Conductor
49
What happens to the current in a wire if the voltage is doubled and the resistance is halved?
