WBBSEClass XPhysical ScienceCurrent Electricity03 Mark2023 Moderate

QQuestion

Write Faraday’s laws of electromagnetic induction.
Mention one advantage of using a LED lamp over an incandescent lamp. [2 + 1]

Exam-ready answer 03 Mark

Answer

Faraday’s law of electromagnetic induction:

  1. Whenever there is a change in magnetic flux linked with a coil, an emf is induced, which lasts as long as the change inmagnetic flux is linked with the coil changes.
  2. The magnitude of the induced emf is directly proportional to the rate of change magnitude flux linked with the coil.

LED lamps are more energy-efficient as they consume significantly less power and last longer compared to incandescent lamps.

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