Question

Where would the image be if the object is moved 15 cm towards the mirror? Draw ray diagram for the new position of the object to justify your answer.

Answer 1

If an object is moved 15 cm towards the mirror, the new object distance (u) is 15 cm less than the original object distance (u).

u = 30 cm

u = 30 − 15

u = 15 cm

Using the mirror formula, the new image distance will be: 

`1/f = 1/v + 1/15`

`1/v = (-2)/15`

`v = (-15)/2`

`v = -7.5` cm