1. What is the unit of electric current?
a) Volt
b) Ampere
c) Ohm
d) Coulomb
Answer: b) Ampere
2. Which particle is responsible for electric current in a metal conductor?
a) Proton
b) Neutron
c) Electron
d) Ion
Answer: c) Electron
3. Ohm’s law states that the current through a conductor is directly proportional to:
a) Resistance
b) Voltage
c) Power
d) Capacitance
Answer: b) Voltage
4. The material that allows electric current to flow easily is called:
a) Insulator
b) Conductor
c) Semiconductor
d) Dielectric
Answer: b) Conductor
5. The potential difference across a conductor is 12 V and current is 3 A. The resistance of the conductor is:
a) 4 Ω
b) 36 Ω
c) 9 Ω
d) 6 Ω
Answer: a) 4 Ω
6. Which of the following is a good insulator?
a) Copper
b) Aluminum
c) Rubber
d) Iron
Answer: c) Rubber
7. The flow of electrons in a circuit is from:
a) Positive to negative terminal
b) Negative to positive terminal
c) High resistance to low resistance
d) Positive to ground
Answer: b) Negative to positive terminal
8. Which law explains the relationship between voltage, current, and resistance?
a) Faraday’s law
b) Coulomb’s law
c) Ohm’s law
d) Lenz’s law
Answer: c) Ohm’s law
9. A material whose resistance decreases with temperature increase is called:
a) Superconductor
b) Semiconductor
c) Insulator
d) Conductor
Answer: b) Semiconductor
10. A device that increases or decreases voltage in AC circuits is called:
a) Transformer
b) Motor
c) Battery
d) Generator
Answer: a) Transformer
11. The total resistance of resistors in series is:
a) Less than the smallest resistor
b) Equal to the largest resistor
c) Sum of all resistances
d) Reciprocal of sum of reciprocals
Answer: c) Sum of all resistances
12. A material with zero resistance at very low temperature is called:
a) Conductor
b) Superconductor
c) Semiconductor
d) Insulator
Answer: b) Superconductor
13. Which device is used to measure electric current?
a) Voltmeter
b) Ammeter
c) Ohmmeter
d) Galvanometer
Answer: b) Ammeter
14. Electric power is calculated by:
a) P = VI
b) P = I²R
c) P = V²/R
d) All of the above
Answer: d) All of the above
15. What is the function of a fuse in an electric circuit?
a) Increase current
b) Protect the circuit
c) Reduce voltage
d) Store energy
Answer: b) Protect the circuit
16. Coulomb is the unit of:
a) Current
b) Charge
c) Resistance
d) Voltage
Answer: b) Charge
17. The current in an electric circuit is 2 A and flows for 5 seconds. The charge passed is:
a) 2 C
b) 5 C
c) 10 C
d) 7 C
Answer: c) 10 C
18. What type of circuit has more than one path for current to flow?
a) Series circuit
b) Parallel circuit
c) Open circuit
d) Short circuit
Answer: b) Parallel circuit
19. In a parallel circuit, the voltage across each resistor is:
a) Different
b) Same
c) Zero
d) Depends on resistance
Answer: b) Same
20. What happens to total resistance if resistors are connected in parallel?
a) Increases
b) Decreases
c) Remains same
d) Becomes infinite
Answer: b) Decreases
21. The device that converts chemical energy into electrical energy is called:
a) Generator
b) Battery
c) Transformer
d) Capacitor
Answer: b) Battery
22. Which of the following is an example of alternating current (AC)?
a) Current from a dry cell
b) Current in household mains
c) Current in a flashlight
d) Current in a battery-operated toy
Answer: b) Current in household mains
23. What is the energy used per second in an electric circuit called?
a) Voltage
b) Current
c) Power
d) Resistance
Answer: c) Power
24. A material that opposes the flow of electric current is called:
a) Conductor
b) Insulator
c) Resistor
d) Capacitor
Answer: c) Resistor
25. Which factor does NOT affect resistance of a wire?
a) Length of wire
b) Material of wire
c) Color of wire
d) Temperature
Answer: c) Color of wire
26. Electric current in metals is due to:
a) Movement of protons
b) Movement of electrons
c) Movement of neutrons
d) Movement of ions
Answer: b) Movement of electrons
27. In a series circuit, if one bulb goes out:
a) All bulbs go out
b) Other bulbs remain on
c) Voltage increases
d) Current decreases but bulbs remain on
Answer: a) All bulbs go out
28. The SI unit of electrical resistance is:
a) Ohm
b) Ampere
c) Volt
d) Joule
Answer: a) Ohm
29. Electric current can be measured using:
a) Ammeter
b) Voltmeter
c) Multimeter
d) Both a & c
Answer: d) Both a & c
30. The work done by 1 coulomb of charge when it moves through a potential difference of 1 volt is called:
a) Current
b) Voltage
c) Electric energy
d) Resistance
Answer: c) Electric energy