Question

If a gas absorbs $200J$ of heat and expands by $500$ cm${}^3$ against a constant pressure of $2\times {10}^{5}N{m}^{-2},$ then the change in internal energy is:

Answer 1

Correct Answer: 100

The correct answer is 100 j.
From first law of thermodynamics,Change in internal energy is$\mathrm{\Delta }U=q-w=q-P\mathrm{\Delta }V$$=200-2\times {10}^5\times 500\times {10}^{-6}$$=100J$Hence, the correct answer is $100J$.