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Lifetimes of the molecules in the excite...

Lifetimes of the molecules in the excited states are often measured by using pulsed radiation source of duration nearly in the nano second range. If the radiation source has the duration of `2` ns and the number of photons emitted during the pulse is `2.5xx10^(15)`, calculate the energy of the source.

A

`8.282 xx 10^(10)` J

B

`4.141 xx 10^(-10)` J

C

`6.262 xx 10^(-9)` J

D

`8.282 xx 10^(-10)` J

Text Solution

Verified by Experts

The correct Answer is:
D
`E = Nhv (because v = (1)/(t) ) , E = (Nh)/(t)`
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