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A bulb of 800 W electrical power has eff...

A bulb of 800 W electrical power has efficiency 6%. It is kept at the centre of a sphere of diameter 20 cm. If surface of this sphere is a perfect reflector then find force exerted on it.

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`F=32xx10^(-8)N`
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KUMAR PRAKASHAN-ELECTROMAGNETIC WAVES-SECTION B NUMERICALS (Numerical From Textual Illustrations)
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