Question

An object of height 5 cm is placed in front of a concave mirror of radius of curvature 40 cm at distance 40 cm find

1)position of the image
2)magnification
3)height of the image ​

Answer 1

Explanation:

focus=radius of curvature/2

f=20cm

using mirror formula

1/f=1/v+1/u

1/v=1/f-1/u

using sign convention

1/v=1/u-1/f

1/v=1/40-1/20

v=-40cm

1) image will be real, inverted and same size as object

2) magnification=-distance of image/distance of object

=40/(-40)

=-1

3) magnification=height of image/height of object

-1=h/5

h=-5cm