Tried this problem for about 2 hrs and no dice...(adsbygoogle = window.adsbygoogle || []).push({});

A spy satellite orbiting at 150 km above the Earth's surface has a lens with a focal length of 3.5 m and can resolve objects on the ground as small as 36 cm; it can easily measure the size of an aircraft's air intake. What is the effective lens diameter, determined by diffraction consideration alone? Assume = 527 nm.

I dont think the 150km matters...

i just did .36 = f*theta and i got theta = .36/3.5

then i did theta = wavelength /d (diameter) and i get like 5.12e-6M

totally wrong...help

btw as soon as someone replies i will prolly reply back since its kinda urgent

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# Homework Help: Diffraction lens diameter Problem

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