Question

when an object is placed at distance of 8cm from a concave mirror its image is fomed at 10cm in front of mirror calculate the focal length of mirror?​

Answer 1

here u =-8 cm

v=-10cm

1/f=(1/v)+ (1/u)

1/f=1/-10-1/8

1/f=-9/40

f=-40/9cm or -4.444 cm