Question

at what value of the angle of incident is shaft of light reflected from the surface of water perpendicular to the refracted shaft​

Answer 1

Answer:

Let PQ be the surface of water and n be the R.I. of water. Let AO is the shaft of light with incident angle θ1 and OB and OC are the reflected and refracted light rays at angles θ1 and θ2 respectively (Fig.).

θ2 = π /2 - θ1

From the law of refraction at the interface PQ

n = sinθ 1 / sin θ 2 = sin θ1 / ( sin π/2 -1 )

or sin θ1 / cos θ 1 = tan θ 1

hence,

θ1 = tan^-1 n

hope it will help you.....

Answer 2

Answer:

ans is. In attachment...........