Simple Machines
Vocabulary:
 Weightthe force of gravity on an object at the surface of a planet. |  Resisitan Armthe distance from the fulcrum to the output force / object. |  Effort Armthe distance from the fulcrum to the input force |
|---|---|---|
 Ideal Mechanical AdvantageThe ratio of the length of the effort arm to the resistant arm of a lever. The ratio of the length of the inclined plane to the height. MA = Effort / Resistance [lever] MA = Length / Height [inclined plane] |  WorkForce exerted on an object that causes it to move. (Work = Force x Distance). |  Input Forcethe force you exert on a simple machine. |
 Output Forcethe force the machine exerts on an object |  Mechanical AdvantageThe ratio of output force to input force. Output Force / Input Force |  Simple MachineA device that makes work easier |
 Forcea push or pull exerted on an object. |  Massthe amount of matter in an object. |
Day 1: Intro to Levers and Ramps
Starter Questions:
1. Work on Vocabulary
We started out with labs today. Each of these labs, one for levers and one for Incline Planes, helped us to better understand how each machine works. Levers are most useful to lift objects that are normally to heavy to shift. Ramps or Incline Planes are also use full to move objects, but not nearly as high. With each of these machines we looked at the ratios between the forces and the ratio of lengths. These become important when we look at it tomorrow.
Day 3: Mechanical Advantage
Start questions
1. Label the parts of a 1st Class lever
2. Give an example of a 3rd class lever
The idea of Mechanical Advantage is quite simple. When using a simple machine you want to you the least amount force and still get force out. We always want to do the least amount of work. There are two equations that can be used to find mechanical advantage. The first is done with the lengths. MA = Effort / Resistance or MA = Output / Input.
The higher the number the greater the mechanical advantage. This means its easier to move the object.
Day 2: Simple Machines
Starter Questions
1. Name 3 simple machines you used this morning
2. If i needed to lift an object with a lever, and it required too much force, what could I do to make it easier?
They really do make our lives easier. These powerful tools are what let acient cultures build things like the Pyramids, Stonehenge and Parthenon. We are looking at how each one of these machines impact our lives and how we still use them every day.
Day 4: Mechanical Advantage Labs
Starter Questions:
Calculate the Mechanical Advantage
1.
30N
3N
16m
4m
Day 5: Work Labs
Starter Questions:
1. Calculate the mechanical advantage.
5 m
25 m
Today we explored Machanical Advantage of 3 differnt simple machines, Levers, ramps and pullys. This let us see how each one is effected by the ratios of Output force over input force.
2 N
22 N
Work is the next step as we work through each of our Physics equations. Work = Force * Distance. Work can only be done on an object is the object is moving. The unit we use for work is the Joule. Once we find the work done on an object we find how much power is needed to do that work. Power = Work / time. The unit for power is the Watt.
