Question
Explain Cassegrain telescpoe with the help of figure.
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Answer
→Figure shows construction of cassegrain telescope. It uses two mirrors. Among them, the concave mirror called the object mirror (main mirror) and the convex mirror is called the secondary mirror.
→An object mirror has a larger focal length and a secondary mirror has a less focal length.
→As shown in figure, rays from a distant object are reflected by the objective mirror and focussed at the principal focus.
→But another small convex mirror is placed in the path of these rays. The rays reflected by this mirror are observed through the eyepiece.
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