Aray of light passes from vacuum into a medium of refractive index m, the angle of incidence is found to be twice the angle of refraction. Then the angle of incidence is

step by sep solution please

Let angle of incidence equal to I.

So angle of refraction will be I/2.

sin I/(sin I/2)=m. (Snell's law)

sin I =nsin I/2

But sin I =2sin I/2cosi/2

After substituting and simplifying,

We get:-

cos I/2=m/2

I/2=cos^-1(m/2)

I=2cos^-1(m/2)