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# Refracting Telescopes

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1. Hello,
Please could I have some help with refraction and telescopes and lenses please- all part of P1.
Thanks a lot
2. I can explain the principle, if you want. Here is a picture to understand.

The objective has a collecting lens, where the parallel light rays are refracting, so they hit each other in a common point, the focus (focal point). The distance between the collecting lense and the focus is the focal length. The same goes for the eyepiece lense too (it is a collecting lense as well). So both lenses have a common focal point, where the image can be observed. As the refracting telescope has a long focal length, it is able to get images which have a long distance to this telescope (so called tele-focal point).*
3. (Original post by Kallisto)
I can explain the principle, if you want. Here is a [url=http://www.pas.rochester.edu/~blackman/ast104/refracting.gif]picture] to understand.

The objective has a collecting lens, where the parallel light rays are refracting, so they hit each other in a common point, the focus (focal point). The distance between the collecting lense and the focus is the focal length. The same goes for the eyepiece lense too (it is a collecting lense as well). So both lenses have a common focal point, where the image can be observed. As the refracting telescope has a *long focal length, it is able to get images which have a long distance to this telescope (so called tele-focal point).*
Thank you, this helps a lot, although the link doesn't seem to be working.
4. (Original post by esha20x)
Thank you, this helps a lot, although the link doesn't seem to be working.
It works. Have just made mistakes to embed the link. The problem is solved, the link has to be worked now.*

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