Can any one suggest a good book on telescopes
What sort of level are you looking for?
Here are some free basic online resources that aren't bad: http://www.celestron.com/c3/images/files/downloads/1297801757_telescopebasics.pdf [Broken]. http://www.physics.udel.edu/~jlp/classweb2/directory/powerpoint/telescopes.pdf
Do you just want to do/learn about observational astronomy? In that case your best bet is to a join a local club or organization. Experience actually doing, and learning from those who do, observational astronomy will greatly speed up the learning process.
If you're interested from an academic standpoint, please clarify.
I want learn the physics of it
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