Question

b. A convex mirror has a focal length of
18 cm. The image of an object kept
in front of the mirror is half the height
of the object. What is the distance of
the object from the mirror?​

Answer 1

Answer: The distance of the object from the mirror is 18 cm.

Step-by-step explanation:

v/u = -1/2

on cross multiplying, v= -u/2

1/f = 1/v + 1/u

f = vu/ v + u

18 = -u^2/2 ÷ u/2

On canceling 2,

18 = -u^2/u

Again On crossmultiplying,

18u = -u^2

u = -18

Please tell me if my answer is wrong.