A train travelling at 20 m/s has 2 000 000 J of kinetic energy. What is the mass of
the train?

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?

An object's buoyant force and weight mean the same thing.a. trueb. false

When the displacement of a mass on a spring is 12a the half of the amplitude, what fraction of the mechanical energy is kinetic energy? at what displacement, as a fraction of a, is the mechanical energy half kinetic and half potential?