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JEE Main20199 Apr 2019Evening ShiftChemistryThermodynamics (C)Actual

During compression of a spring the work done is 10 k J and 2 k J escaped to the surroundings as heat. The change in internal energy, Δ U i n   k J is:

Options

  1. A- 8
  2. B8
  3. C12
  4. D- 12

Correct answer

B. 8

Step-by-step solution

From the first Law of Thermodynamics, ∆ U = q + W     ∆ U = - 2 + 10         q = - 2   k J ;   Heat released   W = + 10   k J ; work done on the system   ∆ U = 8   k J    

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