When a ray of light enters into the medium of refractive index of `mu`, angle of refraction is half of angle of incidence so angle of incidence = ......

Options

A. `2sin^(-1)(mu/2)`
B. `2cos ^(-1)(mu)`
C. `cos^(-1)(mu/2)`
D. `2cos^(-1)(mu/2)`

Answer

A, B, C, D

Explanation

`mu =sini/sinr=(sini)/(sini//2)`
`=(2sin""1/2cos""1/2)/(sin""i/2)`
`therefore mu =2cos""i/2`
`therefore mu/2=cos""i/2`
`i/2=cos^(-1)(mu/2)`
`therefore i= 2cos^(-1)(mu/2)`