Question

A 25 cm long object is placed between two mirrors forming an angle of 90°. What will be the number of images formed?

• A. 8D
• B. Infinite
• C. 25D
• D. 3

Hint:

When two mirrors form a 90° angle, the number of images formed can be calculated using the formula \( N = \frac{360}{\theta} - 1 \). For a 90° angle, the number of images will always be 3.

Answer 1

The Correct Option is D

Step 1: Understanding the concept.
The number of images formed by two mirrors depends on the angle between them. The formula for the number of images formed is given by: \[ N = \frac{360}{\theta} - 1 \] where \( \theta \) is the angle between the mirrors.
Step 2: Applying the formula.
In this case, \( \theta = 90^\circ \). Substituting this value into the formula: \[ N = \frac{360}{90} - 1 = 4 - 1 = 3 \]
Step 3: Conclusion.
The number of images formed by two mirrors at a 90° angle is 3.