Question

An object of 5cm tall is placed at a distance of 10cm from a concave mirror of radius of curvature 30cm , find the nature,position and size of the image

Answer 1

v=?

R= 30 cm

f =15 cm

ho= 5 cm

1/u+1/v=1/f

(-1/10)+(1/v)=(1/15)

1/v=1/15+1/10

1/v=(2+3)/30

1/v =5/30

v= 6 cm

size of the image

m= hi/ho =-v/u

=-6/10 =0.6

0.6=hi/5

hi=3 cm

The image is formed at a distance of 6 cm behind the mirror, virtual, upright and smaller than the object.

size of the image is 3 cm.

Answer 2

-10 cm for convex mirror, the object distance is -ve.

v=?

R= 30 cm

f =15 cm

ho= 5 cm

1/u+1/v=1/f

(-1/10)+(1/v)=(1/15)

1/v=1/15+1/10

1/v=(2+3)/30

1/v =5/30

v= 6 cm

size of the image

m= hi/ho =-v/u

=-6/10 =0.6

0.6=hi/5

hi=3 cm

The image is formed at a distance of 6 cm behind the mirror, virtual, upright and smaller than the object.