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 1 mW and its wavelength is 632.8 nm . The intensity of focussed beam will be

A laser beam can be focussed on an area equal to the square of its wav

1.	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 1 mW and its wavelength is 632.8 nm . The intensity of focussed beam will be
Answer» `1.5 xx 10^(13) W//m^(2)` `2.5 xx 10^(9) W//m^(2)` `3.5 xx 10^(17) W//m^(2) W//m^(2)` None of these Answer :B

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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 1 mW and its wavelength is 632.8 nm . The intensity of focussed beam will be

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