Same chapter3 marksDifficulty: Medium
A person cannot see distant objects clearly. Name the defect, the lens used to correct it, and explain why that lens works.
Refraction through a Lens
3 marksDifficulty: Medium
An object is placed 20 cm from a converging lens of focal length 15 cm. Find the position, nature and magnification of the image.
Original Khojo Papers practice question — not from a past board paper.
Answer
The image is 60 cm from the lens on the other side, real, inverted and three times the size of the object.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Using 1/v − 1/u = 1/f with u = −20 cm and f = +15 cm, 1/v = 1/15 − 1/20 = 1/60, so v = +60 cm. The magnification is v/u = 60/(−20) = −3.
Related questions
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