A short linear object of length lies along the axis of a concave mirror of focal…

PHYSICS · Single correct · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments

Problem

A short linear object of length

b

lies along the axis of a concave mirror of focal length

f

at a distance

u

from the pole of the mirror. The size of the image is approximately equal to (1)

b \left( \frac{u-f}{f} \right)^{1/2}

(2)

b \left( \frac{f}{u-f} \right)^{1/2}

(3)

b \left( \frac{u-f}{f} \right)

(4)

b \left( \frac{f}{u-f} \right)^2