Toy car a is moving at a speed of 1 m/s towards toy car b that is at rest. Toy car a has a mass of 3 kg and car b has a mass of 2 kg. They couple together after collison. At what speed are they moving after the collison?

If a refrigerator is a heat pump that follows the first law of thermodynamics, how much heat was removed from food inside of the refrigerator if it released 380j of energy to the room?

The freezing and boiling point of a substance changes as the air pressure around it changes. for example, at a lower air pressure (higher altitude) it is easier for water molecules to escape from liquid into the air. in a high altitude city such as denver, colorado compared to a sea-level city such as houston, texas, water

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?