Answer:
Convex lens have the ability to converge a parallel beam of light into a point. This point is called the focal point of the convex lens and the distance from the optical centre to the focal point is called the focal length.
Focal length (f) = 10cm = 0.1m
∴ p = 1 / f
p = 1 / 0.1
p = 10 D.
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