Physics for IGCSE & O level - Electricity (Section 1)
1
Which of the following is the most common type of fuse?
إجابة
(B)
Thermal Fuse
2
What happens to the current in a circuit if the voltage is held constant and the resistance is increased?
إجابة
(B)
The current decreases.
3
What happens if the current flowing through a resistor increases?
إجابة
(C)
The power dissipated by the resistor increases.
4
If the length of a wire is doubled, what happens to its resistance (assuming other factors are constant)?
إجابة
(A)
Doubles
5
What is the purpose of the neutral wire in a three-core cable?
إجابة
(A)
To provide a path for the current to return to the source.
6
What is the unit for measuring electrical power?
إجابة
(D)
Watt
7
What is the name of the point where two or more components connect in a circuit?
إجابة
(A)
Node
8
Which of the following is a unit of electrical energy?
إجابة
(C)
Joule
9
What is the unit for measuring electrical charge?
إجابة
(C)
Coulomb
10
What does the abbreviation LED stand for?
إجابة
(A)
Light Emitting Diode
11
What is the effect of adding more resistors in series in a circuit?
إجابة
(B)
The total resistance increases.
12
If two resistors are connected in parallel, and one resistor has a resistance of 10 ohms and the other has a resistance of 20 ohms, what is the total resistance?
إجابة
(B)
6.67 ohms
13
What best describes electric charge?
إجابة
(D)
Properties
14
What is measured in units of Watts?
إجابة
(D)
Power
15
How does the length of a wire affect its resistance?
إجابة
(C)
Longer wire, higher resistance
16
What is the unit for measuring electrical energy?
إجابة
(C)
Joule
17
Which of the following would become charged by rubbing it with a dry, wool cloth?
إجابة
(A)
PVC
18
In a parallel circuit, what happens to the total resistance if you add another resistor?
إجابة
(A)
Decreases
19
What kind of materials are electrical conductors?
إجابة
(A)
Metals
20
What is the role of a double insulated appliance?
إجابة
(A)
It does not have an earth wire
21
What happens to the total resistance in a series circuit if a resistor is replaced with one of a higher resistance value?
إجابة
(A)
The total resistance increases.
22
In an electric circuit, what is the function of an inductor?
إجابة
(B)
To oppose changes in current
23
What is the relationship between current (I), voltage (V), and resistance (R) in a circuit?
إجابة
(A)
V = I * R
24
In a circuit, the battery supplies energy which is transformed to the...
إجابة
(A)
Lamp
25
What is the term for the number of times the direction of current changes per second?
إجابة
(B)
Frequency
26
What are the two types of electric charge?
إجابة
(A)
Positive and negative
27
What will happen if one of the lamps in the series circuit breaks?
إجابة
(B)
All lamps will not light
28
What type of meter is used to measure current?
إجابة
(C)
An ammeter
29
What are the advantages of arranging some circuits in series?
إجابة
B
D
30
What is the relationship between the current and voltage in a resistor, according to Ohm's law?
إجابة
(B)
They are directly proportional.
31
What happens to the brightness of a lightbulb if the voltage across it increases?
إجابة
(B)
The bulb gets brighter.
32
Which circuit setup allows the full battery potential difference (p.d.) to reach each lamp?
إجابة
(B)
Parallel
33
Which of the following is a feature of double insulation?
إجابة
(C)
Provides two layers of insulation
34
How is the resistance of a conductor calculated?
إجابة
(B)
R = V / I
35
What is the function of a transformer?
إجابة
(B)
To change the voltage of an AC supply
36
What is the function of a variable resistor?
إجابة
(B)
To change the current in the circuit.
37
Which of the following is used to step-up (increase) or step-down (decrease) voltage?
إجابة
(C)
Transformer
38
Which of the following is a non-linear circuit element?
إجابة
(C)
Diode
39
What is the equivalent resistance of two 2-ohm resistors connected in parallel?
إجابة
(A)
1 ohm
40
How is the total current related in a parallel circuit?
إجابة
(B)
The total current is the sum of the currents in each branch.
41
What is the purpose of using multiple parallel paths in a circuit?
إجابة
(C)
To provide multiple current paths
42
What safety device is designed to protect appliances from overloads and short circuits?
إجابة
(C)
Fuse
43
What does a light emitting diode (LED) do?
إجابة
(A)
Emits light when a current flows through it.
44
Which component allows current to flow in only one direction?
إجابة
(C)
Diode
45
Which of the following is a typical household appliance that uses a high current?
إجابة
(B)
An electric iron
46
Which of the following is the unit for electrical charge?
إجابة
(C)
Coulomb
47
Which component is designed to limit the current in a circuit?
إجابة
(C)
A resistor
48
Which of the following components is a passive component?
إجابة
(D)
Resistor
49
What is the purpose of a fuse in a circuit?
إجابة
(B)
To protect the circuit from overcurrent
50
What is the main function of a capacitor in a circuit?
