1.

Radius of curvature of plano-convex lens is 10 cm. If its focal length is 30 cm, then its refractive index will be .......

Answer»

1.1
1.22
1.33
1.66

Solution :`R_1=INFTY`f=30 cm`R_2=-10` cm
`1/f=(n-1)(1/R_1-1/R_2)`
`(1)/(30)=(n-1)[(1)/(infty)-(1)/(-10)] implies (1)/(30)=(n-1)((1)/(10)) implies`
`1/3=n-1 thereforen=4/3=1.33`


Discussion

No Comment Found

Related InterviewSolutions