In a region of uniform magnetic inductance `B=10^(-2)`tesla. A circular coil of radius `30 cm` and resistance `pi^(2) ohm` is rotated about an axis which is perpendicular to the direction of `B` and which forms a diameter of the coil. If the coil rotates at `200` r.p.m the amplitude of the alternating current induced in the coil is

Options

A. `4pi^(2)mA`
B. `30 mA`
C. `6 mA`
D. `200 mA`

Answer

C

Explanation

`(E_(0))=nBA omegasin omegat, (E_(0))_(max)=nBA omega`
`I_(0)((E_(0))_(max))/R=(nBA omega)/R`
`=(1xx10^(-2)xxpi(0.30)^(2)xx2pi(200/60))/(pi^(2))`
`=6xx10^(-3)=6 mA`