| A | B |
|---|
| Force | a push or a pull (example in unit Newton's) |
| Net force of an object | the combination of all forces acting on the object |
| Same direction | add |
| Different direction | subtract |
| Balanced or unbalanced | Forces acting on an object can be |
| Balanced Forces | Two or more forces exerted on an object are balanced if they do not cancel each other and they do not cause a change in the object's motion. |
| Unbalanced Force | Their effects don't cancel each other out. |
| Friction | a force that acts to resist sliding between two touching surfaces. |
| The reason you never see objects move with constant velocity unless a net is applied | FRICTION |
| A force that cause your skateboard to stop unless you keep pushing on it | Example of Friction |
| Four types of Friction | sliding, rolling, static, an fluid |
| Sliding Friction | Due to the microscopic roughness of two surfaces and slows down a sliding object |
| Example of Balanced Forces | You and a friend push on an object with the same force in opposite directions and it does not move |
| Example of Sliding Friction | Rubbing your hand against a table top |
| Rolling Friction | friction between the ground and wheels allow the wheel to roll |
| Example of Rolling Friction | Rolling friction keeps the tires on a bike from slipping on the ground. |
| Static Friction | That prevents an object from moving when a force is applied |
| Example of Static Friction | Trying to push a refrigerator across a floor |
| Fluid Friction | Opposes the motion of an object travelling through a fluid |
| Example of Fluid Friction | Book |
