Question

A Vessel contains helium, which expands at constant pressure when 15 kJ of heat is supplied to it. What will be the variation of the internal energy of the gas? What is the work performed in the expansion?

Answer 1

Correct Answer - 9
Here `Delta Q = 15000 J` (Given)
In an isobaric process
`Delta Q = nC_(V) Delta T, Delta U = nC_(V) Delta T` (always)
`(Delta U)/(Delta Q) = (nC_(V) Delta T)/(nC_(P) Delta T) = (1)/(gamma) implies Delta U = (Delta Q)/(gamma)`
or `Delta U = (3)/(5) xx 15 = 9 kJ`