Two thin lenses of power + 4D and –2D are in contact.

Two thin lenses of power + 4D and –2D are in contact. What is the focal length of the combination?

Monjur Alahi

5 views

2025-01-04 04:42

1 Answers

Salim Ahmed Kawsar

Net power, P = P₁ + P₂ = + 4D - 2D = +2D

∴ F = 1/P = 1/2 = 0.50m = 50cm

5 views Answered 2023-02-05 15:29

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