Question

Q.12.An object 3.0cm high is placed perpendicular to the principal axis of a concave lens of focal length
15.0cm. The image is formed at a distance of 10.0cm from the lens.
Calculate:-
(a)Distance at which object is placed,and
(b)Size and nature of the image formed.​

Answer 1

Answer:

Using Lens formula 1/f=1/v-1/u

Focal length of concave mirror= - 15

Given (v) = 10

Find (u)

Putting values in formula

1/u=1/10 + 1/15

1/u= 1/6

Therefore distance of object from mirror is 6 cm.

Now size

Magnification=v/u

=15/6

Size=2.5 Larger than object