JEE Main 2021PhysicsRay OpticsHardNumerical

JEE Main 2021 — Ray Optics Question with Solution

JEE Main 2021 (26 Aug Shift 2)

Question

An object is placed at a distance of 12 cm from a convex lens. A convex mirror of focal length 15 cm is placed on another side of the lens at 8 cm as shown in the figure. The image of the object coincides with the object.

When the convex mirror is removed, a real and inverted image is formed at a position. The distance of the image from the object will be ___ cm

Enter your answer

Show full solutionCorrect answer: 50
Correct answer
50

Step-by-step explanation

For the object to coincide with the image, the light must fall perpendicularly to the mirror. This means that the light will have to converge at C of the mirror. Without the mirror also, the light would coverage at C. So the distance is:=12+8+30=50 cm. 

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About this question

This is a previous-year question from JEE Main 2021, covering the Ray Optics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.