A laser beam has a power of 100 mW. It has an aperture of 5xx10^(-3)m and emits a wavelength 6943 Å. The beam is focused with a lens of focal length 0.1 m. Calculate the areal spread and intensity of the image.

A laser beam has a power of 100 mW. It has an aperture of 5xx10^(-3)m

1.	A laser beam has a power of 100 mW. It has an aperture of 5xx10^(-3)m and emits a wavelength 6943 Å. The beam is focused with a lens of focal length 0.1 m. Calculate the areal spread and intensity of the image.
Answer» ANSWER :`2.87xx10^(-10)m^(2),3.48xx10^(8)WM^(-2)`

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A laser beam has a power of 100 mW. It has an aperture of 5xx10^(-3)m and emits a wavelength 6943 Å. The beam is focused with a lens of focal length 0.1 m. Calculate the areal spread and intensity of the image.

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