hi my name is internal energy. in chemistry, i am written as U. in physics and engineering, i am E. in chemistry, they like to add up my work and heat. because the work is the work that i did. not what the world did on me. in physics, they do my heat minus the work. because the work is the work that the world did on me to increase my energy. and i think i got that backwards. because it is so confusing. why don’t they just add them all up, and let it think the way it is. no more memorizing.