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Light with an energy flux 20 W//cm^2 fal...

Light with an energy flux` 20 W//cm^2` falls on a non-reflecting surface at normal incidence. If the surface has an area of `30 cm^2`. the total momentum delivered ( for complete absorption)during 30 minutes is

A

`36x 10^(5)` kg -m/s

B

`36x 10^(4)` kg m/s

C

`108 x 10^(4)` kg -m/s

D

`1.08 x 10^(7) ` kg -m/s

Text Solution

Verified by Experts

The correct Answer is:
B
`U= phi ` At
Momentum of the incident light = `(U)/(C )`
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Knowledge Check

  • Light with an energy flux of 18W//cm^(2) falls on a non-reflecting surface at normal incidence. The pressure exerted on the surface is

    A
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    B
    `2.50xx10^(-6) N`
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    D
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    B
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    D
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