Question

The image of an object formed by a mirror is of magnification 1. Answer the following questions related to this information giving reason for each :
(a) State the nature of the mirror.
(b) If the image is at a distance of 40 cm from the mirror, where is the object placed ?
(c) Where would the image be formed, if the object is moved 10 cm towards the mirror ?

Got it in a paper. Hope you can answer properly ^_^

Answer 1

a)concave mirror

b)40cm from the mirror on same side as image

c)v= -(40-10)=-30

f=r/2

=-40/2

=-20

mirror formula. 1/v+1/u=1/f

1/u=1/f-1/v

1/u=(1/-20)-(1/-30)

1/u=(-30+20)/600

=-10/600

1/u=-1/60

u=-60

image will be formed 60 cm from mirror on same side object