Given a scientific question, generate a correct answer to it.

Example Input: How much work is done when a force is applied in a different direction than the direction of movement?
Example Output: none

Example Input: What is the term for learning by watching and copying the behavior of someone else?
Example Output: observational learning

Example Input: Heat expansion is a result of the increase of what type of energy, exhibited by molecules bumping together?
Example Output:
kinetic energy