Question

a concave mirror has a focal length of 20cm at what distance from the mirror should a 10 cm tall object be placed so that it forms an image at a distance of 30 cm from the mirror also calculate the size of the image formed

Answer 1

Answer:

HEY! SOLUTION IS GIVEN IN THE ATTACHMENT

HOPE IT HELPS :)

Answer 2

Answer:

First, draw the figure(see file attached below)

For concave mirror, 1/F=1/U+1/V

1/u= 1/-20-1/(-30)

   =1/-20+1/30

   = 3-2/60

   =1/60

as we know u is always negative

so u=  -60

Size of Image=m=-v/u

Size of Image=4/-2

Size= -2 cm