During compression of a spring the work done is 10 kJ and 2 kJ escaped to the surroundings as heat. The change in internal energy, (in kJ) is:
- (A)8✓ Correct
- (B)12
- (C)-12
- (D)-8
Answer: (A)
Solution
By the first law of thermodynamics, . Compressing the spring means work is done on the system, so kJ, while kJ leaking out to the surroundings as heat means kJ. Adding these, kJ.
JEE Main · 2019 · 09 Apr 2019 · Shift 2 · Single correct option