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Electromagnetic Induction — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Induction1 Mark
Question
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b ), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and Rare true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion (A): Acceleration of a magnet falling through a copper ring decreases.
Reason (R): The induced current produced in a circuit always flow in such direction that it opposes the change or the cause that produced it.
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Answer

  1. Both A and R are true and R is the correct explanation of A.

Explanation: 

Both the assertion and reason are true and reason is the correct explanation of assertion. When the magnet falls, the magnetic flux through the copper ring increases and induced e.m.f. is produced in the ring. The induced emf so produced, opposes the motion of falling magnet. Therefore, the acceleration of the falling

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