I would say friction because it requires to surfaces in order for the force to take place
correct me if I'm wrong.
Prompt gamma rays are....
Opportunity cost refers to what you have to give up to buy what you want in terms of other goods or services. When economists use the word “cost,” we usually mean opportunity cost.
The work function is what we call the minimum energy that is required by an electron to leave the metal target in the photoelectric effect.
