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Two lenses of power 3D and -1D are kept ...

Two lenses of power 3D and -1D are kept in contact. What is focal length and nature of combined lens?

A

50 cm, convex

B

200 cm, convex

C

50 cm, concave

D

200 cm, concave

Text Solution

Verified by Experts

The correct Answer is:
A, C
` P = P_(1) + P_(2) = 3 - 1 = 2D`
`F = (1)/(P) = (1)/(2) m = 50 cm`
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