A student pushes horizontally on a book with a force of 2 N, which causes the book to slide at a constant velocity. What is the force of friction on the book?

Which is not a characteristic of a heat pump? a. it is used in air conditioners. b. it uses a refrigerant. c. it requires no work. d. it reverses the normal flow of thermal energy.

How do you tell if someone actually cares about you? and just say they do?

How are the crust and the inner core alike? a) they are both solid. b) they both have the same temperature. c) they are both under the same pressure. d) they are both very close to the center of the earth.