Question

A object is placed at 30 cm on the principle axis of the convex lens from the lens and an image is formed 60 cm from the lens. If focal length of the lens is 20 cm then calculate the magnification.

• A. 0.5
• B. 0.67
• C. 1.5
• D. 2
• E. 3

Answer 1

The correct option is D 2

Given : $u=-30$ cm

The image is formed behind the lens as the object distance is greater than the focal length of the lens.

$⟹$ $v=+60$ cm

$\therefore$ Magnification $m=\frac{-v}{u}=\frac{-\left(60\right)}{-30}=2.0$