A rectangular coil of 100 turns and size `0.1mxx0.05m` is placed perpendicular to a magnetic field of 0.1 T. If the field drops to 0.05 T in 0.05 s, the magnitude of the emf induced in the coil is

Options

A. `sqrt2`
B. `sqrt3`
C. `sqrt(0.6)`
D. 0.5

Answer

D

Explanation

Given, n= 100 turns, A = `0.1xx0.05m^(2)`
`B_(1)=0.1T, B_(2)=0.05T, dt=0.05s`
We know that,
`e=|(-dphi)/(dt)|=|(d)/(dt)("n B A cos"theta)|=|(nAdBcos theta)/(dt)|`
Here, `theta=0`
`therefore" "e=|(nAdB)/(dt)|=|(100xx0.1xx0.05xx(0.1-0.05))/(0.05)|`
`rArr" e = 0.5 V`
None of the option is correct.