At what distance should an object be placed from a convex lens of focal length 18 cm to obain an image at 24 cm from it one the other side? What will be the magnification produced in this case?

Explanation

Here, `u=?, f= 18cm, v = 24 cm, m=?`
from `(1)/(v) -1/u =(1)/(f), - 1/u = (1)/(f) - (1)/(v) =1/18 - 1/24 = (4-3)/(72)=1/72`
`u =- 72 cm`.
As `m = v/u = (-72)/(24)= -3`
Negative sign of m indicates that the image would be inverted.