Question

A concave mirror of focal length 20cm is placed at a distance of 50cm from a wall . How far from a wall should an object to be placed to form it's real image on the wall??​

Answer 1

Answer:

using formula of mirror

Explanation:

1/v - 1/u = 1/f

1/(-50) - 1/u = 1/(-20)

from here u can calculate value of u

Answer 2

Answer:

100mts...............