A very small circular loop of area `5xx10^(-4)m^(2)` , resistance `2Omega` and negligible inductance is initially coplanar and concentric with a much larger fixed circular loop of radius `0.1m` . A constant current of `1A` is passed in the bigger loop and the smaller loop is rotated with angular velocity `omega rad//sec` about a diameter. Calculate (a) the flux linked with the smaller loop, (b) induced emf (c) induced current in the smaller loop, as a function of time.

Explanation

The magnetic field at the centre of the smaller loop is
`B =(mu_(0))/(4 pi) (2pi i)/(a)`
where `i` is the current through the larger top and a is the radius of larger loop. The flux linked through the smaller loop at any instant is `phi` = BA cos `omegat` where A is the area of the smaller loop.
`:.` The induced e.m.f at any instant is given by
`e= -(dphi)/(dt) implies e = BA omega sin omega t= 3.14 xx10^(-9) omega sin omega t`
Current = `1.57 xx10^(-6) omega sin omegat`