What makes some collisions elastic and others inelastic?

If the collision involves bouncing, it is elastic.

If the collision involves sticking together, it is elastic.

If there is no loss of kinetic energy in the collision, it is inelastic.

If there is energy lost in the collision to sound, heat, etc., the collision is inelastic.

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

Madison lives near the ocean. she’s formed a hypothesis that increased concentrations of salt in the air speeds the corrosion of certain metals. if madison plans to test this hypothesis, she will have to deal with the following variables in her experiment: dependent variable: independent variable: one possible confounding variable:

The height of the empire state building is 318 m if a stone is dropped from the top of the building what is the stones velocity just before it strikes the ground