Question

magnification produced by a convex mirror is 1/3,then the distance of the object from mirror is----

Answer 1

Explanation:

1/f = 1/v - 1/u , multiply using by u

⇒

f

u

=

v

u

−

u

u

=

v

u

−1

⇒

f

u

+1=

v

u

⇒

v

u

=

f

u+f

⇒

u

v

=

f+u

f

⇒m∣

u

−v

∣=

f+u

f

given that m=

3

1

So

3

1

=

f+u

f

⇒f+u=3f

⇒

u=2f