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An achromatic telescope objective of fo...

An achromatic telescope objective of focal length 1.5m is consists of two thin lenses of dispersive power 0.050 and 0.075, respectively, placed in contact. Find the focal length of each lens.

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The correct Answer is:
For convex lens: `f = 50 cm, omega = 0.050`, for concave lens: `f = 75 cm, omega = 0.075`
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