JEE Main 2025PhysicsThermal Properties of MatterEasyNumerical

JEE Main 2025Thermal Properties of Matter Question with Solution

JEE Main 2025 (7 Apr Shift 1)

Question

A wire of length 10 cm and diameter 0.5 mm is used in a bulb. The temperature of the wire is and power radiated by the wire is 94.2 W. Its emissivity is where _______
(Given and assume that the emissivity of wire material is same at all wavelength.)

Enter your answer

Show full solutionCorrect answer: 5
Correct answer
5

Step-by-step explanation


Power,




Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Thermal Properties of Matter chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

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