Reflecting telescope optics problem-Angle on the sky to angle on a mirror

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SUMMARY

The discussion centers on calculating the size of the Moon's image formed by the 3.6 m diameter mirror of the Canada-France-Hawaii Telescope, which has a focal length of 8.5 m. The key equation used is the lens formula, 1/s + 1/s' = 1/f, where 's' is the object distance and 's'' is the image distance. The angle subtended by the Moon at the mirror is equivalent to the angle subtended by the image, similar to the principles of refracting telescopes. Participants express confusion regarding the application of these concepts to reflecting telescopes.

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Homework Statement



When viewed from Earth, the Moon subtends an angle of 0.5° in the sky. How large an image of the Moon will be formed by the 3.6 m diameter mirror of the Canada-France-Hawaii Telescope, which has a focal length of 8.5 m?

Homework Equations



1/s + 1/s' = 1/f, but I'm not sure what else.

The Attempt at a Solution



I'm really not sure where to begin. My book only talks about refracting telescopes and we've yet to talk about reflecting telescopes in class. I thought initially it might have something to do with the distance to and radius of the moon but I couldn't figure out how to work those into the problems. I'd appreciate any help you have. Thanks!
 
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The angle the object subtended at the mirror is the same angle that the image subtends - just like for refracting telescopes.
 

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