Light is incident normally on a small plane surface. If the surface is rotated by an angle of 30 about the incident light, does the illuminance of the surface increase, decrease or remain same ? Does your answer change if the light did not fall normally on the surface ?

A ray of light is incidenting normally on a plane mirror. The angle of reflection will be

A ray of light is incident normally on one of the faces of a prism of apex angle 30^@ and refractive index sqrt2 . Find the angle of deviation for the ray of light.

If a ray of light is incident at a glass surface at the Brewster's angle of 60^(@) , then the angle of deviation inside glass is

Light from a point source falls on a small area placed perpendicular to the incident light. if the area is rotated about the incident light by an angle of ~60∘, by what fraction will the illuminance change ?

A ray of light is incident normally on one refracting surface of an equilateral prism . If the refrctive index of a material of the prism is 1.5., then

A beam of white light is incident normally on a plane surface absorbing (70%) of the light and reflecting the rest. If the incident beam carries 10 W of power , find the force exerted by it on the surface .

A parallel beam of monochromatic light of wavelength 500nm is incident normally on a perfectly absorbing surface. The power through any cross- section of the beam is 10 W. Find (a) the number of photons absorbed per second by the surface and (b) the force exerted by the light beam on the surface.

When the light ray is incident normal to the interface between any two media, the angle of incidence is ___________ .

Unpolarised light is incident on a plane glass surface. What should be the angle of incidence so that the reflected and refracted rays are perpendicular to each other? (Given n=1.5)

Say TRUE or False.We see a book because it reflect the light that falls on its surface