Q. 183.8( 10 Votes )
A doctor has prescribed a corrective lens of power + 1.5 D. Find the focal length of the lens. Is the prescribed lens diverging or converging?
The power of this lens is positive (with a plus sign), therefore, this is a convex lens or converging lens. Now,
Power, P =
So, +1.5 =
So, Focal length of lens, f = +66.7 cm.
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