A convex lens is put 10 cm from a light source and it makes a sharp image on a screen, kept 10cm from the lens. Now a glass block (refractive index 1.5) of 1.5 cm thickness is placed in contact with the light source. To get the sharp image again, the screen is shifted by a distance d. Then d is:
a.
0.55 cm away from the lens
b.
1.1 cm away from the lens
c.
0.55 cm towards the lens
d.
0
a.
0.55 cm away from the lens
b.
1.1 cm away from the lens
c.
0.55 cm towards the lens
d.
0
Question ID - 50070 | SaraNextGen Top Answer A convex lens is put 10 cm from a light source and it makes a sharp image on a screen, kept 10cm from the lens. Now a glass block (refractive index 1.5) of 1.5 cm thickness is placed in contact with the light source. To get the sharp image again, the screen is shifted by a distance d. Then d is:
a.
0.55 cm away from the lens
b.
1.1 cm away from the lens
c.
0.55 cm towards the lens
d.
0
A convex lens is put 10 cm from a light source and it makes a sharp image on a screen, kept 10cm from the lens. Now a glass block (refractive index 1.5) of 1.5 cm thickness is placed in contact with the light source. To get the sharp image again, the screen is shifted by a distance d. Then d is:
|
a. |
0.55 cm away from the lens |
b. |
1.1 cm away from the lens |
|
c. |
0.55 cm towards the lens |
d. |
0 |
-
=
f = 5cm
Shift due to slab=t
in the direction of incident ray
=1.5
=0.5
Again,
=
= 10.55 cm