CameraIcon

SearchIcon

MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Combinations of Lenses & Mirrors

A wire gauge ...

Question

A wire gauge is illuminated with blue light and a convex lens forms a sharp image of it on a screen. If now the wire gauge is illuminated with red light, to get a sharp image again the screen must be :

A

moved towards the lens

No worries! We‘ve got your back. Try BYJU‘S free classes today!

B

moved away from the lens

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

C

placed there itself

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

moved to infinity

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B moved away from the lens
Blue light has less wavelength than red light and we know that as wavelength increases deviation decreases. so, for red light, image will be formed at a larger distance. So, screen should be moved a way from lens. Hence correct option is B.

Suggest Corrections

thumbs-up

0

Similar questions

Q. An object is placed

30 c m

away from a convex lens of focal length

10 c m

and a sharp image is formed on a screen. Now a concave lens is placed in contact with the convex lens. The screen now has to be moved by

45 c m

to get a sharp image again. The magnitude of focal length of the concave lens is (in

c m

Q. A student obtained a sharp image of a lighted candle on a screen using a convex lens. Now he wants to focus a distant lamp on a far away electric pole. In which direction should the lens be moved for this purpose with respect to the screen, to get a sharp image on the screen? Justify your answer.

Q. A student obtained a sharp image of a lighted candle on the screen using a convex lens. Now he wants to focus a distant lamp on the screen. In which direction should the lens be moved for this purpose with respect to the screen, to get a sharp image on the screen?

Q. A convex lens is put

10 c m

from a light source and it makes a sharp image on a screen, kept

10 c m

from the lens. Now a glass block (refractive index 1.5) of

1.5 c m

thickness is placed in contact with the light source. To get the sharp image again, the screen is shifted by a distance

d

d

Q. A converging beam of the light forms a sharp image on a screen. A lens is placed in the path of the beam, the lens being

10 c m

from the screen. It is found that the screen has to be moved

8 c m

further away from the lens to obtain a sharp image. Find the focal length and nature of lens.

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Combination of Lenses and Mirrors

PHYSICS

Watch in App

explore_more_icon

Explore more

Combinations of Lenses & Mirrors

Standard XII Physics

Join BYJU'S Learning Program

CrossIcon