If the gas in a container absorbs 275 Joules of heat, has 125 Joules of work done on it, then does 50 Joules of work, what is the increase in the internal energy of the gas?

The increase in the internal energy = 350 J

Explanation:

Given that

Q = 275 J

W = - 125 J

W' = 50 J

W (net) = - 125 + 50 = - 75 J

Sign -

1. Heat rejected by system - negative

2. Heat gain by system - Positive

3. Work done by system = Positive

4. Work done on the system-Negative

Lets take change in the internal energy = ΔU

We know that

Q = ΔU + W (net)

275 = ΔU - 75

ΔU = 275 + 75 J

ΔU=350 J

The increase in the internal energy = 350 J