1. Friction is the force that opposes motion and transforms work into heat. Friction can be decreased by adding things like oil or water onto two surfaces that are rubbing together. Friction can be increased by adding things like sand or grit between two surfaces.
2. Know the three classes of levers:
1st Class— Fulcrum in the middle
2nd Class—Load (output force) is in the middle
3rd Class— Effort (input force) is in the middle
3. Power is work divided by _________ .
4. Work happens when an object is moved a distance by a force. If two forces are going the same direction they add together. If they are going opposite directions they will subtract from each other.
5. Machines make work easier.
6. Why do machines give us less work out than we put in? Where is our work going (what does it become)?
7. Efficiency compares the output of a machine to the input: Efficiency = output work/input work x 100%
8. How do you increase the Mechanical Advantage of a lever, pulley, and inclined plane?
9. Inclined planes (ramps) that are __________ have more Mechanical Advantage.
10. In a diagram, how do you know if forces are balanced or unbalanced?
Also, check out these videos of simple machines!!!
