Question

6 cm high object is place in front of a concave mirror with a radius of curvature of 20 cm. Determine the image height if the object distance is 5 cm.

Answer 1

ANSWER:-

The plane mirror forms same size image as the object and it is erect, laterally inverted and at the same distance as the object from the mirror.Hence the height of the image will be 10 cm only.

It is given that,

Magnification

$m=3</p><p></p><p>m= </p><p>u</p><p>−v</p><p> </p><p> </p><p></p><p> f= </p><p>2</p><p>R</p><p> </p><p> =−18cm</p><p></p><p>It is given that a virtual image three times the size of the object is obtained with a concave mirror. So, v=−3u</p><p></p><p>From mirror’s formula</p><p></p><p>v</p><p>1</p><p> </p><p> + </p><p>u</p><p>1</p><p> </p><p> = </p><p>f</p><p>1</p><p> </p><p> </p><p></p><p>3u</p><p>−1</p><p> </p><p> + </p><p>u</p><p>1</p><p> </p><p> = </p><p>−18</p><p>1</p><p> </p><p> </p><p></p><p>u=−12cm$

The distance of the object from the mirror u=12cm in front of concave mirror.

HOPE it's helps you ❤️