Electro Magnetic Induction And Alternating Currents Question 480

Question: A horizontal ring of radius $ r=\frac{1}{2}m $ is kept in a vertical constant magnetic field 1 T. The ring is collapsed from maximum area to zero area in 1 s. Then the emf induced in the ring is

Options:

A) 1 V

B) $ (\pi /4)V $

C) $ (\pi /2)V $

D) $ \pi ,V $

Show Answer

Answer:

Correct Answer: B

Solution:

  • $ | . e | .=B\frac{dA}{dt} $ $ | . e | .=B\frac{(A_{2}-A_{1})}{(t_{2}-t_{1})}\Rightarrow | . e | .=\frac{1( \frac{\pi }{4}-0 )}{(1-0)} $ $ e=\frac{\pi }{4}V $


NCERT Chapter Video Solution

Dual Pane