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A 1.5 kW (kilo-watt) laser beam of wavel...

A 1.5 kW (kilo-watt) laser beam of wavelength 6400 Å is used to levitate a thin aluminium disk of same area as the cross section of the beam. The laser light is reflected by the aluminium disk without any absorption. The mass of the foil is close to -

A

`10^(-9) kg`

B

`10^(-3) kg`

C

`10^(-4) kg`

D

`10^(-6) kg`

Text Solution

Verified by Experts

The correct Answer is:
D
`F = (2P)/(C)`
`mg = (2xx 1.5 xx 10^(3))/(3 xx 10^(8))`
`m = 10^(-6) kg`
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