Question

How does the magnitude of magnification changes if an object placed at center of curvature of a concave mirror is moved towards the focus?

• A. It decreases
• B. It increases
• C. It remains constant
• D. It becomes zero

Answer 1

The correct option is B It increases

(1)

(2)

(3)



As the object moves towards focus, the height of the image increases as shown in these ray diagrams.

We know that magnification, $m=\frac{\text{height of image}}{\text{height of object}}$

As the height of the image increases, the numerator increases, which in turn leads to the increase in the magnitude of magnification.