How are simple machines similar and different?

Simple Machine A machine that does work with only one movement. Compound Machine A machine made up of a combination of simple machines. Inclined Plane A flat, sloped surface. Wedge An inclined plane that moves Screw An inclined plane wrapped around a cylinder or post. Lever Any rigid rod or plank that pivots, or rotates about a point. Fulcrum The point about which the lever pivots. Wheel & Axle Two circular objects of different diameters attached so that they rotate together. Pulley Consists of a grooved wheel with a rope or cable wrapped over it.

Simple Machine Does work with only one movement. Does work with only one movement. Device that makes doing work easier. Device that makes doing work easier. The amount of work does not change. The amount of work does not change.

Simple Machines Inclined Plane Inclined Plane Wedge Wedge Screw Screw Lever Lever Wheel and axle Wheel and axle Pulley Pulley

Who am I? I am any rigid rod or plank. I am any rigid rod or plank. I have a point at which I pivot called a fulcrum. I have a point at which I pivot called a fulcrum. My mechanical advantage is equal to the distance from my fulcrum to the input (effort) force divided by the distance from the fulcrum to the output (resistance) force. My mechanical advantage is equal to the distance from my fulcrum to the input (effort) force divided by the distance from the fulcrum to the output (resistance) force. I have classes based on the position of my fulcrum. I have classes based on the position of my fulcrum. I cannot reduce the amount of work. I cannot reduce the amount of work.

The fulcrum in located between the input (effort) force and the output (resistance) force. The fulcrum in located between the input (effort) force and the output (resistance) force. The closer the fulcrum is to the resistance or load, the less effort it takes to lift the load. The closer the fulcrum is to the resistance or load, the less effort it takes to lift the load.

1 st Class Lever

In all second class levers the output (resistance) force is between the fulcrum and the input (effort) force. In all second class levers the output (resistance) force is between the fulcrum and the input (effort) force. The load is in the middle (wheelbarrow). The load is in the middle (wheelbarrow).

2 nd Class Lever

The input (effort) force is between the fulcrum and the output (resistance) force. The input (effort) force is between the fulcrum and the output (resistance) force. Can you find a 3 rd class lever on you body? Can you find a 3 rd class lever on you body?

3 rd Class Lever

Who am I? I have two circular objects of different sizes that rotate together. I have two circular objects of different sizes that rotate together. One full revolution of either part, causes one full revolution of the other part. One full revolution of either part, causes one full revolution of the other part. I have a point where both of my parts rotate called the fulcrum. I have a point where both of my parts rotate called the fulcrum. I cannot reduce the amount of work. I cannot reduce the amount of work. I can be a bicycle or a doorknob I can be a bicycle or a doorknob

Wheel and Axle The mechanical advantage equals the radius of the wheel divided by the radius of the axle. The mechanical advantage equals the radius of the wheel divided by the radius of the axle. The wheel travels a greater distance, but it requires less force from the axle. The wheel travels a greater distance, but it requires less force from the axle. The wheel and axle is a rotating version of a lever. The wheel and axle is a rotating version of a lever.

Who am I? I can be used with a rope or chain wrapped around me. I can be used with a rope or chain wrapped around me. I can reduce the input (effort) force needed to lift a load (output force) every time you add another machine just like me. But as you add more of me, you also increase the distance you have to pull the rope. I can reduce the input (effort) force needed to lift a load (output force) every time you add another machine just like me. But as you add more of me, you also increase the distance you have to pull the rope. I give you a mechanical advantage by changing the direction of the input force or by reducing the amount of input (effort) force needed. I give you a mechanical advantage by changing the direction of the input force or by reducing the amount of input (effort) force needed. I am a version of a wheel, which is a type of lever. I am a version of a wheel, which is a type of lever. I cannot reduce the amount of work. I cannot reduce the amount of work.

Pulley The more pulleys that are used the less effort required to lift the load and the slower the load is lifted off the ground. The more pulleys that are used the less effort required to lift the load and the slower the load is lifted off the ground. If one pulley is used a person could not lift more than their weight. Effort and resistance force are equal. If one pulley is used a person could not lift more than their weight. Effort and resistance force are equal. If two pulleys are used the effort is only half of the resistance force. 50N =100N If two pulleys are used the effort is only half of the resistance force. 50N =100N

Who am I? I am a flat, sloped surface. I am a flat, sloped surface. I can reduce the amount of input (effort) force needed to move and object, but I also increase the distance you must move it. I can reduce the amount of input (effort) force needed to move and object, but I also increase the distance you must move it. The longer I am the less input force is needed to move and object. The longer I am the less input force is needed to move and object. I cannot reduce the amount of work. I cannot reduce the amount of work.

Inclined Plane The mechanical advantage is equal to the length of the inclined plane divided by its height. The mechanical advantage is equal to the length of the inclined plane divided by its height.

Who am I? I change the direction of the input force. I change the direction of the input force. I can to used for splitting wood and rocks, or raising heavy objects. I can to used for splitting wood and rocks, or raising heavy objects. I am an inclined plane that moves. I am an inclined plane that moves. I have slanting sides ending in a sharp edge. I have slanting sides ending in a sharp edge. I cannot reduce the amount of work. I cannot reduce the amount of work.

Wedge The mechanical advantage equals the length of either slope divided by the thickness of the big end. The mechanical advantage equals the length of either slope divided by the thickness of the big end. The greater the distance of the wedge the less effort force needed. The greater the distance of the wedge the less effort force needed. Examples are a tooth, axle, chisel, and door stop. Examples are a tooth, axle, chisel, and door stop.

Who am I? I have a central core with a groove wrapped around it. I have a central core with a groove wrapped around it. My mechanical advantage is found by dividing my circumference by my pitch. Pitch is the number if treads per inch. My mechanical advantage is found by dividing my circumference by my pitch. Pitch is the number if treads per inch. I cannot reduce the amount of work? I cannot reduce the amount of work? I am an inclined plane. I am an inclined plane.