Q. 5

# A simple microscope is rated 5 X for a normal relaxed eye. What will be its magnifying power for a relaxed farsighted eye whose near point is 40 cm?

Answer :

Given data-

Near point of the relaxed farsighted eye,D = 40cm

Magnification of microscope, m = 5

Least distance of distinct vision for a normal eye = 25cm

For relaxed eyes, the image will be formed at infinity.

Hence, the magnifying for m for simple microscope for normal adjustment (normal eye) will be-

Now, for a relaxed far sighted eye with D=40cm, the magnifying power will be-

Hence, the magnifying power of simple microscope for far sighted eye will be 8X

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