A convex and a concave mirror of radii 10 cm are placed facing each other and 15 cm apart. An object is placed exactly between them. If the reflection first takes place in concave and then in convex mirror the position of the final image will be

Options

A. on the pole of the convex mirror
B. on the pole of the concave mirror
C. at a distance of 10cm from the convex mirror
D. at a distance of 5cm from the concave mirror

Answer

a.

Explanation

For a concave mirro,
`u=-(15)/(2)cm, v=?`
`f=(10)/(2)cm=-5cm`
`(1)/(v)=(1)/(f)-(1)/(u)-(1)/(-5)-(1)/(-15//2)`
`=(1)/(5)+(2)/(15)=(-1)/(15)`
or `v=-15cm`
Clearly, the position of the final image is on the pole of the convex mirror.