Question

A thin converging lens of refractive index of 1.5has a focal power of 5D . When this lens immersed in a liquid it acts a diverging lens of focal length of 100cm. The refractive index of liquid is

Answer 1

Explanation:

1/f=(n-1)1/r1-1/r2

1/5=0.5*x

1/100=(n-1)x

100/5=0.5/n-1

n=1.025