Delta U

[Emily Glaser 1F]

Delta U means change in internal energy, but what does this mean in simple terms? When is delta U = 0?

[kaushalrao2H]

Delta U represents a system's internal energy, or total store of energy in a system. If delta U is zero, then there has been no energy transfer (work or heat) between the system and surroundings.

[Michelle Dong 1F]

Since delta U = q + w, if delta U is 0, then q would equal w. This means that the heat transferred to and from a system is equal to the work done by or on a system. I may be wrong, though; correct me if I am!

[Andrea ORiordan 1L]

I believe Michelle is correct, with the important distinction that q would equal -w or -q would equal w. The sum of the net work done on/by a system and the heat transferred to/from a system would have to be zero-- those two values would have to cancel each other out.