| A | B |
|---|
| force | a push, pull, |
| addition | forces in the same direction combine by ? |
| subtraction | forces in opposite directions combine by ? |
| unbalanced forces | cause a change in motion |
| balanced forces | opposite in direction and equal in size |
| friction | force that opposes motion |
| decreasing mass or decreasing force | two ways to increse acceleration |
| inertia | tendency of matter to resist a change in motion |
| Newton's 1st law of motion | an object at rest will remain at rest and an object in motion will remain in motion at constant velocity unless acted upon by an unbalanced force. |
| force of gravity | mass x acceleration |
| 9.8 m/sec/sec | acceleration due to gravity at the surface of the Earth |
| gravity | force of attraction that exists between all objects in the universe |
| fluids | all liquids and gases are _____ |
| newton | unit for force |
| strength and direction | a force is described by its _______ and its __________ |
| gravity | force that pulls falling objects toward Earth |
| balanced forces | never change the object's motion |
| law of universal gravitation | all objects in the universe attract each other by the force of gravity |
| arrow | symbol used to show force |
| net force | overall force on an object after all the forces are added together |
| start, stop, change direction | 3 things that unbalanced forces can cause an object to do |
| zero | net force of adding equal forces going in opposite directions |
| joules | unit for energy |
| gravitational force | mass multiplied by the acceleration of gravity |
| gravitational potential energy | energy related to an object's height |
| elastic potential energy | depends on the spring force constant and the velocity the spring is moving |
| newtons | unit for "k" in the elastic potential energy formula |
