Assertion (A): A metal ring is kept on a cardboard on top of a fixed current carrying solenoid. If current in the solenoid is switched off, the upward reaction of card board on the ring will increase.
Reason (R): Induced current in the ring will be in the same direction as in the solenoid.
(1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)
(2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(3) (A) is true but (R) is false
(4) Both (A) and (R) are false
Solution:
When solenoid current is switched off, flux decreases. Induced current in the ring flows in the same direction as solenoid current (Lenz's Law), causing attraction. This increases the upward reaction.
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