Forces+Study+Guide

Here's what you need to know for the forces test....

What is a force? What condition is necessary for a force to cause a change in motion? What is the difference between balanced and unbalanced forces? How do you calculate net force (same direction, opposite directions)? What is friction? Give several examples of friction. Give several examples of why friction is bad AND good. What is gravity? What is the relationship between mass and gravity? What is the relationship between distance and gravity? How is gravity measured? What is the difference between weight and mass? What is the relationship between weight and mass? What is air resistance? What is terminal velocity? What is free fall? Where can free fall happen? What is centripedal force? What forces are at work with orbiting objects? Why do astronauts appear to be weightless? What is projectile motion?