Two gases A and B are separated by a partition. Gas A contracts, having 730j of work done on it. 140j of energy are transferred from B to A. By how much does the internal energy of gas A change?
The total energy transferred to gas A is the sum of the work done on it and the energy transferred from gas B:
Total energy transferred to gas A = Work done on gas A + Energy transferred from gas B
Total energy transferred to gas A = 730 J + 140 J
Total energy transferred to gas A = 870 J
The change in internal energy of gas A is equal to the total energy transferred to it:
Change in internal energy of gas A = Total energy transferred to gas A
Change in internal energy of gas A = 870 J
Therefore, the internal energy of gas A changes by 870 J.
To determine the change in internal energy of gas A, we need to consider the work done on gas A and the energy transferred from gas B.
The change in internal energy (ΔU) of a system can be calculated using the first law of thermodynamics:
ΔU = Q - W
where ΔU is the change in internal energy, Q is the heat transferred to the system, and W is the work done on or by the system.
In this case, gas A contracts, meaning that work is done on gas A, so W is positive (+730 J). Additionally, 140 J of energy are transferred from gas B to gas A, so Q is positive (+140 J).
Substituting the values into the equation, we have:
ΔU = 140 J - 730 J
ΔU = -590 J
Therefore, the internal energy of gas A changes by -590 J.