Physicshard · Past Paper

A person can see objects clearly only between 50 cm and 200 cm. What lens is required to see distant objects?

AConvex, f = 50 cm
BConcave, f = 200 cm
CConcave, f = 50 cm
DConvex, f = 200 cm

✓ Correct Answer: BConcave, f = 200 cm

To see distant objects (u=infinity), the far point must be shifted. Using lens formula for v = -200cm gives f = -200cm (concave).

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