12+Olivia+Marsden

__Simple Machines__

GLOSSARY:
 * **Effort** - the force required to move an object.
 * **Load** - the object and its weight.
 * **Work -** when you exert a force on an object that causes the object to move some distance.
 * **Compound Machine** - two or more machines working together to make work easier.
 * **Gears** - two toothed wheels fit together either directly or through a chain or belt so one wheel will turn the other.
 * **Inclined Plane** - a sloping surface, such as a ramp, that can be used to alter the effort and distance involved in doing work.
 * **Lever** - a straight rod or board that pivots on a point known as a fulcrum. The fulcrum can be moved depending on the weight of the object to be lifted or the force you wish to exert.
 * **First Class Lever** - has the fulcrum in the centre. One end lifts an object up just as far as the other end is pushed down.
 * **Second Class Lever** - has the load in the centre.
 * **Third Class Lever** - has the effort and load on the same side of the fulcrum, with the effort in the middle. The effort is always more than the load.
 * **Pulley** - a wheel that usually has a groove around the outside edge. This groove is for a rope or belt to move around the pulley. Pulling down the rope can lift an object attached to the rope.
 * **Screw** - an inclined plane wrapped around a shaft or cylinder. This inclined plane allows the screw to move itself or to move an object or material surrounding it when rotated.
 * **Simple Machine** - a machine with few or no moving parts. They make work easier.
 * **Wedge -** two inclined planes joined back to back. They are used to split things.
 * **Wheel and Axle** - a wheel and axle has a larger wheel (or wheels) connected by a smaller cylinder (axle) and is fastened to the wheel so that they turn together. When the axle is turned, the wheel moves a greater distance than the axle, but less force is needed to move it.
 * **Force** - the energy exerted or brought to bear on an object. Push and pull refers to the direction of the force. Everything around you is pushing or pulling, and being pushed and pulled. Whenever you push on something, it pushes back. When you increase the distance of movement, you use less force. This is Newton’s Third Law of Motion.
 * **Gravity** - a force that pulls objects towards each other.
 * **Mechanical Advantage** - the ratio of output of force to input of force, the number of times a machine increases a force exerted on it.
 * **Input Force** - the force you exert on a machine.
 * **Output Force** - the force a machine exerts on an object.

MECHANICAL ADVANTAGE

How much faster and easier a machine makes your work is called the mechanical advantage of that machine. It is the number of times a machine multiplies your effort force. To find the MA of a machine, you can divide the resistance force by the effort force, resulting mostly in the resistance force being the weight of the object in Newtons.

INCLINED PLANES

To find the MA of an inclined plane, divide its length by its height. MA = length / height



100m
 * 1. What is the height of the inclined plane?**

3,000m
 * 2. What is the length of the inclined plane?**

MA = 3,000 / 100 =30
 * 3. What is the mechanical advantage of the inclined plane?**

EF = resistance force / effort force = 15,000 / 30 =500N
 * 4. How much effort force would be needed to push the dump truck up the mountain?**