Question

A gas in a cylinder with a moveable piston is heated with 94 J of energy, causing the piston to rise. If the internal energy of the system increases by 30 J, how much work is done by the gas?

Answer 1

`64J`

Explanation:

From the First law of thermodynamics we know,when some amount of heat energy(`dQ`) is supplied to the gas,it utilizes some of it in increasing the internal energy(`dU`) and some is used in expanding i.e work done(`dW`) by the gas,

so, `dQ =d U + dW`

So,given, `dQ=94 J` and `dU=30 J`

So, `dW = 94-30=64 J`