Question

An object is placed at a distance of 10cm from a spherical mirror and the image formed at distance of 30 cm from the mirror on the same side as the object.Find the nature and the fical length of the mirror.

Answer 1

magnification= -(-30)/(-10) = -3
image is real and 3 times of object.

1/f = 1/(-30)+1/(-10)
1/f = -(4/30)
f = -30/4
f= -7.5 cm

focal length = 7 .5cm. concave mirror.