Question

A concave mirror of radius of 30cm produces and image three times in size of the object the distance of the object from the mirror is?​

Answer 1

$\\ \sf\longmapsto m=\dfrac{-v}{u}$

• v is image distance and u is object distance.

$\\ \sf\longmapsto 3=\dfrac{-v}{30}$

$\\ \sf\longmapsto -v=30(3)$

$\\ \sf\longmapsto v=-90cm$