Question

4.an object is placed 15 cm from a
convex mirror of radius of
curvature 90 cm. Calculate
position of the image.
​

Answer 1

Ans. u - 15 cm

c - 90cm

f - 90÷2 - 45 cm

v - ?

So the answer may be 11.5 cm

Answer 2

Explanation:

here, u=15

F=90/2= -45

we know that 1/f=1/v+1/v

=1/ -45=1/v+1/15

=1/ -45 -1/15 =1/v

= - 1/45 -3/46=1/v

= -2 -13/45=1/v

=- 4/45=1/v

=v= - 45/4

=v = -11.25cm

now magnification = - v/u

= -(-11.25)/15

=0.75