JEE Main 2019PhysicsDual Nature of MatterMediumMCQ

JEE Main 2019 — Dual Nature of Matter Question with Solution

JEE Main 2019 (10 Apr Shift 2)

Question

Light is incident normally on a completely absorbing surface with an energy flux of  25 W cm-2 . If the surface has an area of  25 cm2 , the momentum transferred to the surface in 40 min time duration will be:

Choose an option

Show full solutionCorrect option: B
Correct answer
B5.0×10-3 N s

Step-by-step explanation

The power of the incident light is P=25  W cm-2×25 cm2
=625 W
Energy incident per second, E=hcλ=625 J
Momentum incident per second, p=Ec=hλ=625c
∴ Total momentum transferred to the surface =625c×40×60
=5×10-3 N s

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About this question

This is a previous-year question from JEE Main 2019, covering the Dual Nature of Matter 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.