Question:medium

A concave mirror is used to form an image of an object. The object distance (u) is 30 cm and the image distance (v) is 15 cm. Calculate the focal length (f) of the mirror.

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Always remember the sign convention: for mirrors, real objects and real images are formed in front of the mirror, meaning their distances (\(u\) and \(v\)) are negative. Concave mirrors have a negative focal length.

Updated On: May 9, 2026

-10 cm
-30 cm
10 cm
30 cm

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The Correct Option is A

Solution and Explanation

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A concave mirror is used to form an image of an object. The object distance (u) is 30 cm and the image distance (v) is 15 cm. Calculate the focal length (f) of the mirror.

Show Hint

The Correct Option is A

Solution and Explanation

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