JEE PHYSICS MCQ: RAY OPTICS

1 Medium

1 of 1

Application +4 | -1

An object and a screen are kept at a distance of

120 \mathrm{~cm}

. A lens is kept between them so that a real image is formed on the screen for two different positions of the lens. Difference between the positions of the lens is

60 \mathrm{~cm}

. The focal length of the lens is

View answer and explanation

Correct option: A

22.5 \mathrm{~cm}

Option C (

2: 1

) is correct because the ratio of rotational kinetic energies is determined by the ratio of their moments of inertia about their diameters.

More Questions from RAY OPTICS

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In refraction, light waves are bent on passing from one medium to the second medium, because, in the second medium A double convex lens is made of glass which has its refractive index 1,45 for violet rays and 1.50 for red rays. If the focal length for violet ray is

20 \mathrm{~cm}

, the focal length for red ray will be Which light rays undergoes two internal reflection inside a raindrop, which of the rainbow is formed? A piece of plane glass is placed on a word with letters of different colours. The letters which appear minimum raised are A dentist has a small mirror of focal length

16 {~mm}

. He views the cavity in the tooth of a patient by holding the mirror at a distance of

8 {~mm}

from the cavity. The magnification is All of the following statements are correct except