state SI units of power of a lens. A convex lens has a focal length of 100 cm. Calculate its power.

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Solution

Power of a lens is defined as the reciprocal of focal-length. Its SI unit is Diopter (D), which is actually reciprocal of 1 meter.
Power of lens=1/Focal length (in metres)
Since, F=100 cm=1m
So, P=1/1=1 D

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state SI units of power of a lens. A convex lens has a focal length of 100 cm. Calculate its power.

Power of a lens is defined as the reciprocal of focal-length. Its SI unit is Diopter (D), which is actually reciprocal of 1 meter. Power of lens=1/Focal length (in metres) Since, F=100 cm=1m So, P=1/1=1 D

Power of a lens is defined as the reciprocal of focal-length. Its SI unit is Diopter (D), which is actually reciprocal of 1 meter.
Power of lens=1/Focal length (in metres)
Since, F=100 cm=1m
So, P=1/1=1 D