Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Heat and Thermodynamics question

2023 · 15 Apr · Shift 1 · Q58
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Heat and Thermodynamics
  5. /2023 · 15 Apr · Shift 1 · Q58

Heat and Thermodynamics question

2023 · 15 Apr · Shift 1 · Q58

JEE MainPhysicsHeat and ThermodynamicsMCQ+4 / −1
A thermodynamic system is taken through cyclic process. The total work done in the process is : JEE Main 2023 (Online) 15th April Morning Shift Physics - Heat and Thermodynamics Question 120 English
  1. A
    100 J100 \mathrm{~J}100 J
  2. B
    Zero
  3. C
    300 J300 \mathrm{~J}300 J
  4. D
    200 J200 \mathrm{~J}200 J
View written solutionFree

Correct answer: QUESTION IS INCOMPLETE; NET WORK IN A CYCLIC PROCESS CANNOT BE NUMERICALLY DETERMINED WITHOUT ADDITIONAL DATA (SUCH AS HEAT SUPPLIED OR AREA ENCLOSED IN A P-V DIAGRAM).

  1. In a cyclic thermodynamic process, the system returns to its initial state.

  2. Since internal energy is a state function, the net change in internal energy over one complete cycle is:

ΔU=0\Delta U = 0ΔU=0
  1. From the first law of thermodynamics:
Q=ΔU+WQ = \Delta U + WQ=ΔU+W

Over a cycle, this becomes:

Q=WQ = WQ=W

So, the net work done in a cyclic process is equal to the net heat supplied.

  1. However, in this question, no PPP-VVV graph or heat data is provided. Therefore, the only universally true conclusion for a cyclic process is:
  • ΔU=0\Delta U = 0ΔU=0
  • but work done need not be zero.

  1. The numerical value of work done cannot be determined from the given information alone.

  2. Hence, among the given options, none can be uniquely justified from the statement alone. So the stored answer 300 J300\,\text{J}300J cannot be concluded from the provided data.

  3. Also note:

  • Option B (Zero) is incorrect in general, because in a cyclic process net work can be nonzero.
  • Options A, C, and D are all specific numbers, but no data is given to choose among them.

Therefore, the question as presented is incomplete.

PreviousNext

More from Heat and Thermodynamics

  • A flask contains Hydrogen and Argon in the ratio 2:1 by mass. The temperature of the mixture is 30∘C. The ratio of average kinetic energy per molecule of the two gases ( K argon/K hydrogen) is : (Given:…2023 · MCQ
  • 1 g of a liquid is converted to vapour at 3 × 10 5 Pa pressure. If 10% of the heat supplied is used for increasing the volume by 1600 cm 3 during this phase change, then the increase in internal energy in the process will be :2023 · MCQ
  • Given below are two statements : Statement I : The temperature of a gas is −73∘ C. When the gas is heated to 527∘ C, the root mean square speed of the molecules is doubled. Statement II : The product of pressure and volume of…2023 · MCQ
  • A hole is drilled in a metal sheet. At 27∘C, the diameter of hole is 5 cm. When the sheet is heated to 177∘C, the change in the diameter of hole is d×10−3 cm. The value of d will be ​…2023 · Numerical
  • Let γ1​ be the ratio of molar specific heat at constant pressure and molar specific heat at constant volume of a monoatomic gas and γ2​ be the similar ratio of diatomic gas. Considering the diatomic gas molecule as a rigid…2023 · MCQ
  • In an Isothermal change, the change in pressure and volume of a gas can be represented for three different temperature; T3​>T2​>T1​ as :2023 · MCQ
  • The root mean square velocity of molecules of gas is2023 · MCQ
  • Match List I with List II Choose the correct answer from the options given below : Includes table2023 · MCQ