Question

an object is placed on the principal axis of a concave mirror of focal length 10cm at a distance of 8.0 cm from the pole then the position and nature of the image
a) 40 cm real
b) 40 cm virtual
c) 20 cm real
d) 20 cm virtual​

Answer 1

Answer:

Light incident from particle P will be reflected at mirror

u=−5cm,f=−

2

R

=−20cm

v

1

+

u

1

=

f

1

v

1

=+

3

20

cm

This image will act as object for light getting refracted at water surface

So, object distance d=5+

3

20

=

3

35

cm

below water surface,

After refraction, final image is at

d

′

=d(

μ

1

μ

2

)

=(

3

35

)(

4/3

1

)

=

4

35

=8.75cm

≈8.8cm