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NEET 2026
Exam
NEET
Year
2026
Subject
Physics
Chapter
Thermodynamics

NEET 2026 · Physics · Thermodynamics

In an adiabatic expansion, the temperature of one mole of an ideal...

In an adiabatic expansion, the temperature of one mole of an ideal monatomic gas (γ=5/3\gamma=5/3) decreases from 6060K to 5050K. The work done by the gas in the process is :
(Take the universal gas constant as R=8.3R=8.3 J mol−1^{-1} K−1^{-1})

Options

  1. A166166 J
  2. B41.541.5 J
  3. C8383 J
  4. D124.5124.5 J

Correct answer

D. 124.5124.5 J

Step-by-step solution

The work done by an ideal gas in an adiabatic process is given by the formula:

W=nR(T1−T2)γ−1W = \dfrac{nR(T_1 - T_2)}{\gamma - 1}

Given values are:
n=1n = 1 mole
R=8.3R = 8.3 J mol−1^{-1} K−1^{-1}
T1=60T_1 = 60 K
T2=50T_2 = 50 K
γ=53\gamma = \dfrac{5}{3}

Substituting these values into the formula:

W=1×8.3×(60−50)53−1W = \dfrac{1 \times 8.3 \times (60 - 50)}{\dfrac{5}{3} - 1}

W=8.3×1023W = \dfrac{8.3 \times 10}{\dfrac{2}{3}}

W=83×32W = \dfrac{83 \times 3}{2}

W=2492=124.5W = \dfrac{249}{2} = 124.5 J

Answer: 124.5124.5 J
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