Electromagnetic Induction, one of the pivotal chapters in class 12 physics, provides a bridge between the world of electricity and magnetism, illuminating how they influence each other. It’s the principle behind many modern-day technologies, from electric generators to wireless charging systems. To assess your understanding and make your journey more engaging, here are 15 simple MCQs crafted especially for beginners. Let’s electrify our knowledge!
1. Who discovered electromagnetic induction?
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Explanation:
Michael Faraday discovered electromagnetic induction in 1831.
2. Electromagnetic induction is the process by which:
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Explanation:
Electromagnetic induction refers to the generation of an electric current by changing the magnetic field.
3. Faraday’s Law is related to:
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Explanation:
Faraday's Law relates the induced electromotive force to the rate of change of magnetic flux.
4. The unit of magnetic flux is:
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Explanation:
The SI unit of magnetic flux is Weber.
5. If the magnetic flux remains constant, the induced EMF will be:
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Explanation:
The induced EMF is proportional to the rate of change of magnetic flux. If the flux remains constant, the rate of change is zero, thus no induced EMF.
6. Lenz’s law states that an induced current will:
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Explanation:
Lenz’s law states that the direction of the induced current is such that it opposes the change causing it.
7. A solenoid with a soft iron core acts as:
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Explanation:
A solenoid with a soft iron core acts as an inductor, storing energy in its magnetic field.
8. The phenomenon of electromagnetic induction is:
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Explanation:
Electromagnetic induction describes a process, and thus is neither scalar nor vector.
9. Self-induction is a phenomenon in which:
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Explanation:
Self-induction refers to the property of a coil to oppose any change in the current flowing through it by inducing an EMF in itself.
10. Transformers work on the principle of:
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Explanation:
Transformers work on the principle of mutual induction between two coils.
11. Eddy currents can be reduced by using:
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Explanation:
Using laminated cores in machines and transformers can minimize eddy currents.
12. The induced EMF in a coil is maximum when the plane of the coil is:
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Explanation:
The induced EMF is maximum when the plane of the coil is perpendicular to the direction of the magnetic field.
13. The magnitude of induced EMF can be increased by:
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Explanation:
The magnitude of induced EMF is directly proportional to the speed of relative motion between the coil and the magnet.
14. The phenomenon where a change in the magnetic field within a closed loop induces a current is called:
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Explanation:
A change in magnetic field within a closed loop induces a current due to the phenomenon of electromagnetic induction.
15. The coils used in AC generators are wound on:
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Explanation:
In AC generators, coils are wound on a soft iron core to maximize the induced EMF.