magnetic effect of electric current mcqs

1. Magnetic field lines emerge from

1. South pole

2. North Pole

3. Center of magnet

4. None of the option

Answer: (b) North Pole

Explanation: Magnetic field lines emerge from the north pole and terminate at the south pole.

2. Magnetic field is a

1. Scalar quantity

2. Vector quantity

3. Dimensionless quantity

4. None of the option

Answer: (b) Vector quantity

Explanation: Since the magnetic field has both magnitude and direction, it is considered as a vector quantity.

3. Overloading happens due to ——————.

1. Short circuits

2. Decrease in power supply

3. Increase in power supply

4. Option (a) and (c)

Answer: (d) Option (a) and (c)

Explanation: Increase or decreases in the power supply causes overloading.

4. Which of the following is used to detect the presence of current in a circuit?

1. Meter bridge

2. Sonometer

3. Galvanometer

4. Electric motor

Answer: (c) Galvanometer

Explanation: Galvanometer is a device used to direct the presence of current in a circuit.

5. The small gap in the electric circuit is known as

1. Cell

2. Load

3. Switch

4. Wires

Answer: (c) Switch

Explanation: A switch is ideally used to open or close a circuit.

6. Unit of electric power may also be expressed as

1. Watt second

2. Ampere hour

3. Volt ampere

4. Kilowatt hour

Answer: (c) Volt ampere

Explanation: The unit of electric power may also be expressed as Volt ampere.

7. ——————– is a closed-loop or path formed by the network of electrical components, where electrons flow.

1. Electric Potential

2. Electric Circuit

3. Electric Path

4. Electric Difference

Answer: (b) Electric Circuit

Explanation: Electric Circuit is a closed loop. Current flows in a closed circuit.

8. ———————– is the device used to convert electrical energy into mechanical energy.

1. Galvanometer

2. Ammeter

3. Electric motor

4. Potentiometer

Answer: (c) Electric motor

Explanation: Electric motor is a device used to convert electrical energy into mechanical energy.

9. The potential difference between a live wire and a neutral wire is ——————.

1. 100 V

2. 280 V

3. 220 V

4. 0 V

Answer: (c) 220 V

Explanation: The potential difference between a live wire and a neutral wire is 220 V.

10. The force exerted on a current-carrying wire placed in a magnetic field is zero when the angle between the wire and the direction of the magnetic field is ——————.

1. 180 degree

2. 45 degree

3. 90 degree

4. 60 degree

Answer: (a) 180 degree

Explanation: We know that sin 180 is 0 and the force exerted on a current-carrying wire that is placed in a magnetic field is zero.