A coil having n turns and resistance `R Omega` is connected with a galvanometer of resistance `4R Omega`. This combination is moved in time t seconds from a magnetic field `W_(1)` weber to `W_(2)` weber. The induced current in the circuit is

Options

A. `-(W_(2)-W_(1))/(5Rnt)`
B. `-(n(W_(2)-W_(1)))/(5rt)`
C. `-((W_(2)-W_(1)))/(Rnt)`
D. `-(n(W-(2)-W_(1)))/(Rt)`

Answer

B

Explanation

`i=(e)/(R )=-(-N)/(R )(varphi_(2)-varphi_(1)))/(Deltat)=(-n(W_(2)-W_(1)))/(5Rt)`