Question:medium

If two thin lenses with focal lengths of +10 cm and +20 cm are placed in contact, what is the total power of the combination?

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Remember to always convert focal lengths to meters (or use the $100/f$ formula for cm) before calculating Power. Power is additive only for thin lenses in contact.

Updated On: May 9, 2026

10 D
5 D
15 D
30 D

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The Correct Option is C

Solution and Explanation

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If two thin lenses with focal lengths of +10 cm and +20 cm are placed in contact, what is the total power of the combination?

Show Hint

The Correct Option is C

Solution and Explanation

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