Physics for IGCSE & O level - Electricity (Section 3)
1
Which of the following components is found in a circuit and used to turn the circuit on and off?
پاسخ دهید
(C)
Switch
2
Which of the following is a good conductor of electricity?
پاسخ دهید
(C)
Copper
3
In a series circuit, if the resistance increases, what happens to the current?
پاسخ دهید
(B)
The current decreases.
4
What is the effect of temperature on the resistance of a semiconductor?
پاسخ دهید
(B)
Resistance decreases with increasing temperature.
5
If a 60W bulb and a 100W bulb are connected in parallel, which bulb will be brighter?
پاسخ دهید
(B)
The 100W bulb
6
In a parallel circuit, how is the total current related to the current through each branch?
پاسخ دهید
(C)
The total current is the sum of the currents in each branch.
7
Which of these appliances typically draws the highest current?
پاسخ دهید
(C)
An electric kettle
8
Which of these will increase the resistance of a wire?
پاسخ دهید
(D)
Increasing the length of the wire.
9
What is the relationship between power and current, given a constant voltage?
پاسخ دهید
(A)
Power is directly proportional to current.
10
Which of these devices is used to convert electrical energy into light?
پاسخ دهید
(C)
A light bulb
11
What is the difference between a series circuit and a parallel circuit in terms of current flow?
پاسخ دهید
(A)
Current is constant in a series circuit, but divides in a parallel circuit.
12
What component is used to convert electrical energy into light?
پاسخ دهید
(C)
Light bulb
13
In a parallel circuit with two resistors, if the current through one resistor is 2A and the current through the other is 3A, what is the total current supplied by the battery?
پاسخ دهید
(D)
5 A
14
What is the purpose of the neutral wire in a mains cable?
پاسخ دهید
(A)
To carry the current back to the source.
15
Which of these is a correct way of calculating voltage (V)?
پاسخ دهید
(B)
V = I * R
16
What type of current is supplied by a battery?
پاسخ دهید
(B)
DC
17
Which safety device is designed to open a circuit automatically when the current exceeds a certain value?
پاسخ دهید
(C)
Fuse
18
What is the effect on the resistance of a wire if you increase its cross-sectional area?
پاسخ دهید
(B)
Resistance decreases
19
What do conductors allow?
پاسخ دهید
(A)
Flow of electrons
20
What is measured in amperes?
پاسخ دهید
(B)
Current
21
If the voltage is constant, what happens to the current if the resistance increases?
پاسخ دهید
(B)
It decreases
22
What is the energy needed to move a unit charge between two points?
پاسخ دهید
(B)
Potential difference
23
What is the formula relating charge, current, and time?
پاسخ دهید
(B)
Charge = Current * Time
24
Which circuit arrangement is typically used for household wiring?
پاسخ دهید
(B)
Parallel
25
What is the total resistance of two 10-ohm resistors connected in series?
پاسخ دهید
(C)
20 ohms
26
What does the symbol on a lamp mean in a circuit diagram?
پاسخ دهید
(D)
A device that converts electrical energy into light
27
Which of the following components does NOT need an earth wire for safety?
پاسخ دهید
(D)
Double-insulated appliance
28
What are the two main types of electric circuits?
پاسخ دهید
(A)
Series and Parallel
29
What is the purpose of a switch in a circuit?
پاسخ دهید
(C)
To open or close the circuit
30
Which of these is the correct formula for calculating power (P)?
پاسخ دهید
(A)
P = V x I
31
What is the relationship between voltage (V), current (I), and resistance (R) in a circuit?
پاسخ دهید
(B)
V = I * R
32
What happens to the total power in a parallel circuit if one branch burns out?
پاسخ دهید
(B)
Decreases
33
What happens to the total resistance if two resistors are connected in series?
پاسخ دهید
(A)
The total resistance is the sum of the two resistors.
34
What is the formula for calculating power?
پاسخ دهید
(B)
P=V*I
35
Which part of a three-pin plug connects to the earth wire?
پاسخ دهید
(C)
The earth pin
36
What happens to the brightness of a lamp in a series circuit if the voltage of the battery is increased?
پاسخ دهید
(B)
Brightness increases
37
If two resistors (R1 and R2) are connected in parallel, and R1 = R2, what is the total resistance compared to either resistor?
پاسخ دهید
(C)
Half of either
38
What happens to the total power dissipated in a series circuit if you add more resistors?
پاسخ دهید
(A)
Increases
39
Which formula represents Ohm's law?
پاسخ دهید
(A)
V = I * R
40
What is the SI unit of electromotive force (EMF)?
پاسخ دهید
(B)
Volt
41
Which component is used to change AC voltage levels?
پاسخ دهید
(C)
Transformer
42
What type of current does a domestic electrical supply in many countries provide?
پاسخ دهید
(B)
Alternating Current (AC)
43
In a parallel circuit, if one branch opens (breaks the circuit), what happens to the other branches?
پاسخ دهید
(C)
The current in the other branches remains the same.
44
What does the fuse protect the electrical circuit against?
پاسخ دهید
(B)
Excess current
45
What happens to the total resistance of a circuit if more resistors are added in parallel?
پاسخ دهید
(B)
Decreases
46
How is the total resistance in a series circuit affected if one of the resistors is removed?
پاسخ دهید
(B)
Decreases
47
Which of the following is NOT a good conductor?
پاسخ دهید
(C)
Rubber
48
What is the name given to static electricity?
پاسخ دهید
(D)
electrostatic
49
Which is the formula relating power (P), current (I), and resistance (R)?
پاسخ دهید
(C)
P = I^2 * R
50
What is the total resistance of two resistors, one of 3 ohms and the other of 6 ohms, connected in parallel?
