Question

A rod of length 12 cm is placed horizontally along the principle axis of a concave mirror of focal length 24 cm. The end near to the pole is at centre of curvature. Find the length of image of rod​

Answer 1

Explanation:

Given = object distance = -12cm

focal length = -24cm(because focal length of concave mirror always measured as negative because it is left side of the mirror)

Using mirror formula,

1/f =1/v+1/u

1/24 = 1/v - 1/12

1/-24 + 1/12 = 1/v

-1+2/-24=1/v

1/-24=1/v

v=-24

hence the length of the rod is -24cm