Q17DQ

Question

When a converging lens is immersed in water, does itsfocal length increase or decrease in comparison with the value inair? Explain.

Step-by-Step Solution

Verified
Answer

When the lens in water focal length is increase.

1Step 1: definition of focal length

The term focal length may be defined as the distance between the center of mirror and its focus.

2Step 2: Explain the reason of question

The refractive index of the lens and surrounding material are closer when lens in water. The light less bent when it entered and exits the lens and focal length increase when lens in water.


Hence, when the lens in water focal length is increase.