A point source (S) of light having power 500 W is kept at the focus of a lens of aperture diameter d. The focal length of the lens is2d/3. Assume that 40% of the incident light energy is transmitted through the lens and the complete transmitted light is incident normally on a perfectly reflecting surface placed behind the lens. Calculate the force on the reflecting surface.

A point source (S) of light having power 500 W is kept at the focus of

1.	A point source (S) of light having power 500 W is kept at the focus of a lens of aperture diameter d. The focal length of the lens is2d/3. Assume that 40% of the incident light energy is transmitted through the lens and the complete transmitted light is incident normally on a perfectly reflecting surface placed behind the lens. Calculate the force on the reflecting surface.
Answer» ANSWER :`1.33 XX 10^(-7) N`

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