question_answer

A point source of light is placed at the centre of curvature of a hemispherical surface. The radius of curvature is R and the inner surface is completely reflecting The force on the hemisphere due to the light falling on it if the source emits a power P [c is the speed of light ]

A) \[\frac{2P}{C}\]

B) \[\frac{P}{2C}\]

C) \[\frac{5P}{2C}\,\]

D) \[\frac{4P}{3C}\,\]