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A laser beam can be focussed on an area ...

A laser beam can be focussed on an area equal to the square of its wavelength. A `He-Ne` laser radiates energy at the rate of `1mW` and its wavelength is `600 nm`. The intensity of focussed beam will be

A

`3.2xx10^(9)W//m^(2)`

B

`2.8xx10^(13)W//m^(2)`

C

`2.7xx10^(9)W//m^(2)`

D

`3.2xx10^(13)W//m^(2)`

Text Solution

Verified by Experts

The correct Answer is:
C
`I=(P)/(A)=(P)/(lambda^(2))`
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