A small object is placed on the principal axis of a concave spherical mirror of…

PHYSICS · Subjective · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments

Problem

A small object is placed on the principal axis of a concave spherical mirror of radius

20\ \text{cm}

at a distance of

30\ \text{cm}

. By how much does the image position alter when a parallel-sided glass slab of thickness

6\ \text{cm}

and refractive index

1.5

is introduced between the centre of curvature and the object? The parallel sides are perpendicular to the principal axis.