JEE PHYSICS MCQ: RAY OPTICS

1 Medium

1 of 1

Application +4 | -1

A convex glass lens

\left( {{\mu _g} = 1.5} \right)

has a focal length of 8 cm when placed in air. What is the focal length of the lens when it is immersed in water

\left( {{\mu _g} = \frac{4}{3}} \right)

View answer and explanation

Correct option: A

32 cm

Option A (32 cm) is correct because the focal length increases when the lens is immersed in water, and the calculation using the lens maker's formula yields 32 cm.

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