A 3 cm tall object is placed at a distance of 7.5 cm from a convex mirror of focal length 6 cm. Find the location, size and nature of the image.

Answer

A, B, C, D

Explanation

Given `AB=3cm, =-7.5 cm, f=6 cm`
Using `1/v+1/u=2/f`
`rarr 1/v=1/f-1/u`
Putting has according to sign convention
`=1/v=1/v-1/9-7.5)`
`1/6+1/7.5=3/10`
`rarr v=10/3 cm `
Magnification `=m=/v=10/(7.5x3)`
`rarr (A'B')/(AB)=10/(7.5xx3)`
`rarr AB=100/75=4/3=1.33cm`
`:.` Image wil form at a distance of `10/3` cm from the pole and image is 1.33 cm (virtul and erect).