A physicist works in a laboratory where the magnetic field is `2T`. She wears a necklace enclosing area `0.01 m^(2)` in such a way that the plane of the necklace is normal to the field and is having a resistance `R=0.01Omega`. Because of power failure, the field decays to `1T` in time `10^(-3)` seconds.
The what is the total heat produced in her necklace?`(T=tesla)`

Options

A. `10J`
B. `20J`
C. `30J`
D. `40J`

Answer

A

Explanation

`H=(V^(2)t)/(R )` and `V=(N(B_(2)-B_(1))Acostheta)/(t)`
`V=(1xx(1-2)xx0.01xxcos0^(@))/(10^(-3))=10V`