Question

A thin convex lens of focal length ${}^{\prime }{f}^{\prime }$ made of crown glass is immersed in a liquid of refractive index ${\mu }_1({\mu }_1>{\mu }_2)$ where ${\mu }_c$ is the refractive index of the crown glass. The convex lens now is

• A. A convex lens of longer focal length
• B. A convex lens of shorter focal length
• C. A divergent lens
• D. A convex lens of focal length $({\mu }_c>{\mu }_1)f$

Answer 1

The correct option is C A divergent lens

Since ${\mu }_{liquid}>{\mu }_{lens}$ the nature of lens changes from convex into diverging lens.