Answers

2016-03-17T20:33:43+05:30
When an object is placed infront of a plane-mirror an image is formed behind the mirror at a distance equal to the distance of the object from the mirror.That is distance of the image from the mirror= V = -U.
from the law of distances, 1/f = 1/U + 1/V
1/f = 1/U - 1/U = 0
That is f = infinity. (Where f is the focal length of the mirror,U is distance of the object from the mirror,and V is the distance of the image from the mirror .)

R = 2 X f


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