A runaway train that has a mass of 70,989 kg and is travelling at a speed of 69 m/s. How much work does Superman do in slowing the train down to a controllable speed of 18?

If the speed of a particle triples ,by what factor does its kinetic energy increase?

Which best represents the law of conservation of mass ?

Sodium chloride, nacl, is formed when a sodium atom transfers its electron to a chlorine atom. the difference in charge between the two atoms creates a(n) attraction that bonds them together.