# I got the answer but I suppose I did not understand the question very well [duplicate]

This question is an exact duplicate of:

See as per the question, The Inductor pretty much will induce emf due to magnetic field and not due to other coil/current nearby. Thus I used $$E= - d(phi(t))/dt$$ as the induced emf.

Then using (magnitude of q=CV) I put V=E thus getting q(t)=C . d(phi(t))/dt

Also I took phi(t) = B.A.coswt arbitrarily where at t=0, phi = B.A And so I got the 2nd option. Please help me. Is my solution correct? Also can you help with 4th option? I presume its not related to the question at all?

Edit:- Sorry with my Latex. I dont know how to write it properly.

## marked as duplicate by Aaron Stevens, PM 2Ring, Norbert Schuch, Qmechanic♦Aug 13 at 10:52

This question was marked as an exact duplicate of an existing question.