Which is more useful for storing thermal energy: this metal or an equal weight of water? explain?

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

One form of energy can be another type of energy. a. created to form b. transformed into c. destroyed and then created to form

How to tell if two objects are in thermal equilibrium 1.the objects have the same temperature 2.the objects are the same size 3.the objects are touching each other 4.the objects temperatures are changing