JEE Main 2025PhysicsMechanical Properties of FluidsHardNumerical

JEE Main 2025Mechanical Properties of Fluids Question with Solution

JEE Main 2025 (28 Jan Shift 2)

Question

A thin transparent film with refractive index 1.4 , is held on circular ring of radius 1.8 cm . The fluid in the film evaporates such that transmission through the film at wavelength 560 nm goes to a minimum every 12 seconds. Assuming that the film is flat on its two sides, the rate of evaporation is ____ .

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Show full solutionCorrect answer: 54
Correct answer
54

Step-by-step explanation

For a thin film interference, a fringe for transmission is formed. When

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About this question

This is a previous-year question from JEE Main 2025, covering the Mechanical Properties of Fluids 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.