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The number of photons (lambda=6630 Å) th...

The number of photons `(lambda=6630 Å)` that strike per second on a totally reflecting screen (as shown in figure ), so that a force of 1 N is exerted on the screen , is approximately

A

`10^(23)`

B

`10^(27)`

C

`10^(25)`

D

`10^(26)`

Text Solution

Verified by Experts

The correct Answer is:
B
`F = (dp)/(dt) rArr F = ((2P sin theta)/(Deltat))`
`rArr F = 2nsintheta` [`n =` number of photon]
`rArr 1N = 2[n] (h)/(lambda) sin 30^(@) rArr n = 10^(27)`
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