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JEE PHYSICS MCQ: RAY OPTICS

1 Medium

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Application +4 | -1

A slide projector has to project a

35 \mathrm{~mm}

slide

(35 \mathrm{~mm} \times 23 \mathrm{~mm})

on a

2 \mathrm{~m} \times 2 \mathrm{~m}

screen at a distance of

10 \mathrm{~m}

from the lens. What should be the focal length of the lens in the projector?

View answer and explanation

Correct option: B

17.19 cm

Option B (17.19 cm) is correct because it is the focal length calculated using the lens formula and the given magnification and distance.

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