Focal length of the lens

Thread starter syllll_213
Start date Apr 15, 2025

Apr 15, 2025

syllll_213

Homework Statement: An object is in a distance of 14 cm from a converging lens. The lens produces a virtual image at a distance 18 cm from the object.

What is the focal length of the lens (in cm).

Relevant Equations: 1/f = 1/di + 1/do

I attempted and keyed in the answer as 63 but I was graded wrong. What am I missing?

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Apr 15, 2025

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syllll_213 said:

Homework Statement: An object is in a distance of 14 cm from a converging lens. The lens produces a virtual image at a distance 18 cm from the object.

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