Same chapter3 marksDifficulty: Medium
A concave mirror of focal length 15 cm forms an image twice the size of the object and real. Find the object distance.
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3 marksDifficulty: Medium
An object is placed 15 cm from a convex lens of focal length 10 cm. Find the position and magnification of the image.
Original Khojo Papers practice question — not from a past board paper.
Answer
The image is 30 cm from the lens on the other side, and the magnification is −2.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
From 1/v − 1/u = 1/f with u = −15 and f = +10, 1/v = 1/10 − 1/15 = 1/30, so v = 30 cm and m = v/u = −2.
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