Question

An object is placed on a convex mirror at 60 m from the mirror it's radius of curvature is 40cm the object starts moving towards the mirror at 20 m/s find the average speed of image after a time interval of 2 seconds

Answer 1

Answer: 2.5 m/s

Explanation:

distance of object from the pole is 60 cm

focal length is 20 cm

u = -60         f = 20     v = ?

1/v+1/u = 1/f  ; 1/v - 1/60 = 1/20

v= 15 cm

after 2 sec the distance covered is  speed*time = 20*2=40cm

the distance of the object from the pole is 20 cm

1/v+1/u=1/f

1/v-1/20 = 1/20

1/v = 40/20*20

v= 10 cm

image moves from 15cm to 10cm in 2 sec

average speed = 5/2 = 2.5 m/s

Answer 2

Your Answer is in two Attachment....

Hope it helps you dear......xd