Question

A converging lens has a focal length of 24 cm. How far from the lens should an object be placed to get a real image with a magnification of 2.2 and a virtual image with a magnification of 2.2?

a. a real image with a magnification of 2.2

b. a virtual image with a magnification of 2.2

Answer 1

A converging lens has a focal length of 24 cm

f= 24 cm

for real image:

s'/s=-2.2
s'= -2.2s

use:
1/f=1/s'-1/s
1/24 = -1/2.2s -1/s
s= -34.91cm
Ans: 34.91 cm

for virtual image:

s'/s= 2.2
s'= 2.2s

use:
1/f=1/s'-1/s
1/24 = 1/2.2s -1/s
s= -13.09 cm
Ans: 13.09 cm

I hope help you !!