Learn

Saturday, 31 October

JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 17 March 2021, Shift 1, Physics Q3

Question 3 of 90 in this shift, Physics question 3 of 30, Section A.

A Carnot's engine working between 400 K and 800 K has a work output of 1200 J per cycle. The amount of heat energy supplied to the engine from the source in each cycle is :
  1. (1)2400 JOfficial answer
  2. (2)1600 J
  3. (3)3200 J
  4. (4)1800 J

Official answer

Option 1

NTA final key.

Same idea in other shifts

Asked 15× in all
  1. 8 Apr 2023, Shift 2 · Q34Work done by a Carnot engine operating between temperatures 127∘127^\circC and 27∘27^\circC is 2 kJ. The amount of heat transferred to the…EasySingle correct
  2. 12 Apr 2023, Shift 1 · Q38An engine operating between the boiling and freezing points of water will have A. efficiency more than 27%. B. efficiency less than the…MediumOther
  3. 25 Jul 2022, Shift 2 · Q45Let η1\eta_1 is the efficiency of an engine at T1\mathrm{T_1} = 447°C and T2\mathrm{T_2} = 147°C while η2\eta_2 is the efficiency at…EasySingle correct
  4. 28 Jul 2022, Shift 1 · Q37A Carnot engine has efficiency of 50%. If the temperature of sink is reduced by 40∘40^\circC, its efficiency increases by 30%. The…MediumSingle correct
  5. 30 Jul 2022, Shift 2 · Q7A Carnot engine is operating between the two reservoirs of temperature 227 ∘^\circC and 127 ∘^\circC respectively. If the engine…EasySingle correct
  6. 24 Jun 2022, Shift 1 · Q47A Carnot engine whose heat sinks at 27∘27^\circC, has an efficiency of 25%. By how many degrees should the temperature of the source be…MediumSingle correct
  7. 24 Jun 2022, Shift 2 · Q35A Carnot engine takes 5000 kcal of heat from a reservoir at 727∘C727^{\circ}C and gives heat to a sink at 127∘C127^{\circ}C. The work done by…EasySingle correct
  8. 26 Jun 2022, Shift 1 · Q37The efficiency of a Carnot's engine, working between steam point and ice point, will be :EasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.