Heat transfer Q and work done W are always energy in transit, whereas internal energy E is energy

Question

stored in a system. Give an example of each type of energy, and state specifically how it is either in
transit or resides in a system.

Answer 1

I thought internal energy was usually called U

Q is like heat flowing into a pot from the flame beneath

W is like a piston moving and pushing a connecting rod

U is like the water in the pot turning from cold to hot, storing energy provided by the flame beneath