An object is moving towards a concave mirror of focal length 24 cm. When it is at a distance of 60 cm from the mirror, its speed is `9 cm//s`. The speed of its image at that instant , is

Explanation

(b) `0.27 (cm)/(s),(c) 3.1 xx 10^(3) (cm)/(s), (d) 6.7 (cm)/(s)`