JEE Main 2019PhysicsThermodynamicsHardMCQ

JEE Main 2019 — Thermodynamics Question with Solution

JEE Main 2019 (10 Jan Shift 1)

Question

Three Carnot engines operate in series between a heat source at a temperature T1 and a heat sink at temperature T4 (see figure). There are two other reservoirs at temperature T2 and T3, as shown, with T1>T2>T3>T4. The three engines are equally efficient if:

Choose an option

Show full solutionCorrect option: C
Correct answer
CT2=T12T413;T3=T1T4213

Step-by-step explanation

η1=1-T2T1

η2=1-T3T2

η3=1-T4T3

Given η1= η2= η3

T2T1=T3T2=T4T3

T22=T1T3 ....(1)

T32=T2.T4 ....(2)

From (1) and (2)

T3=T1 T421/3,T2=T12T41/3

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About this question

This is a previous-year question from JEE Main 2019, covering the Thermodynamics 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.