Question

Raj strikes a beam of laser light on an extremely hot plate and observes the patch on point A as shown in figure. If the plate is replaced with an extremely cold plate, where will the patch of light now be formed?

• A. Towards the right of A
• B. Towards the left of A
• C. At A

Answer 1

The correct option is A Towards the right of A

When the plate is extremely hot, the region close to the plate is less dense as compared to the region far above. Therefore, the light ray bends away from the normal and strikes at point A.
When the plate is replaced by an extremely cold plate, the region close to the plate will be denser as compared to the region far above. Therefore, the light will bend towards the normal.
Hence, the light will strike the plate at a point towards the right of A.