A gas is compressed from a volume of 2 m to a volume of 1 m at a constant pressure of 100 N/m. Then it is heated at constant volume by supplying 150 J of energy. As a result, the internal energy of the gas :
← JEE Main 2014 · 19 Apr · Shift 1
PhysicsSingle correct+4 / -1Question 12 of 90
JEE Main 2014 · 19 Apr · Shift 1, Physics question 12
Answer and worked solution
Official answer: A
Compression at 100 N/m² through 1 m³: 100 J of work is done on the gas. Heating at constant volume adds 150 J.
The key treats the compression as having no heat exchange, giving J, an increase of 250 J.
(The question does not actually say whether heat flowed during the compression; for an ideal gas, an isobaric compression releases heat, so the key's reading is the one intended.)