Question

Q.3. An object is placed at 60 cm from the
vex lens of focal length 30 cm. If the height of
the object is 3 em, then determine the position
and nature of the image.​

Answer 1

Answer:

Here, u = -60 cm, f = 30 cm, h = 3 cm

Image distance can be calculated as follows :

v

1

−

u

1

=

f

1

or,

v

1

+

60

1

=−

30

1

or,

v

1

=

30

1

−

60

1

=

60

2−1

=−

60

1

or, v=60 cm

Now, image height can be calculated as follows :

M=

h

h

′

=

u

v

or, M=

3

h

′

=

−60

60

or, h

′

=−3 cm

This shows that image is of the same size. Negative sign shows that image is real and inverted.