A coil of area `10cm^2` and 10 turns is in magnetic field directed perpendicular to the plane and changing at a rate of `10^8 gauss//s`. The resistance of coil is `20Omega`. The current in the coil will be

Options

A. `5 A`
B. `0.5A`
C. `0.05A`
D. `5xx10^(8)A`

Answer

A

Explanation

Induced current is given by
`i=(e)/(R)=-(N(dphi//dt))/(R)=-(N)/(R)((dphi)/(dt))`
`=(10xx10^(8)xx10^(-4)xx10^(-4)xx10)/(20)=5A`