Question

An object is placed 20 cm away from concave mirror of focal length 15cm, calculate position of image.​

Answer 1

Explanation:

We can see Object distance (u) is 20cm.

Focal length (f)= 15 cm.

By using sign convention , in concave mirror,

u and f both -(ve).

There is a formula 1/u+1/v=1/f

Buy using this formula we can find the v.

v= 1/f - 1/u

v= -1/15 - 1/20

v= -60cm

So we can now say that the position of the image will be 60 cm from the mirror.