# Simple Machines Group JJ.

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Simple Machines Group JJ

My Simple Machine The Pulley

Definition of PULLEY: A simple machine consisting essentially of a wheel with a grooved rim in which a pulled rope or chain can run to change the direction of the pull and thereby lift a load.

Pulley Pic. 1

Pulley Pic. 2

1 2 3 Mechanical Advantage .5 times 4 5 Pulley Pic. 3

Compound Machine (with pulley)
Wheel and Axle

Compound Machine 2

Compound Machine 3

Resources en.wikipedia.org/wiki/Pulley
library.thinkquest.org/27948/pulley.html library.thinkquest.org/J002079F/pulley.htm

By: Amber Schaeffer ( : Pd. 12
Inclined Plane By: Amber Schaeffer ( : Pd. 12

What is it? An inclined plane is a flat surface whose endpoints are at different heights A slanted surface that raises an object. When an inclined plane is used, less force is needed than if an object would go straight up.

Ex. 1 - Ramps

Ex. 2 -Chutes

Ex. 3 - Slides

Equations & Examples The equation for the mechanical advantage (MA) is MA=s/h S = slope H = height S H

Equations & Examples 2 To find the magnitude of two components you use: F u = mg(sin ) F = mg(cos ) F u F

Sources Used http://en.wikipedia.org/wiki/Inclined_plane

Simple Machines: Lever
Alicia Snyder Pd. 12

LEVERS A lever is a simple machine that makes work easier.
Levers involve moving a load around a pivot using a force.

ORDERS/ CLASSES In a Type 1 Lever, the pivot (fulcrum) is between the effort and the load. In a Type 2 Lever, the load is between the pivot (fulcrum) and the effort. In a Type 3 Lever, the effort is between the pivot (fulcrum) and the load.

Mechanical Advantage The mechanical advantage of a lever is the ratio of the length of the lever on the applied force side of the fulcrum to the length of the lever on the resistance force side of the fulcrum. Mechanical Advantage= Effort Arm/Resistance Arm

10:1 Resistance Arm Effort Arm

Compound machines Wheel Barrel: Lever Wheel and Axle

Compound Machines Scissors: Lever Screw Wedge

Compound machines Bicycle Screws Wheel and axle Lever Pulley

Bibliography  used this site for mechanical advantage  used this site for classes and definition of a lever used for compound machines ^ used to find levels of levers ^found info on levers

Simple Machines The Screw
Kati Myers Pd. 12 2/26/2009

What is a screw? A screw is actually an inclined plane that is wrapped around a cylinder and has a wedge at the tip. The incline plane is the thread that goes all the way around the screw. They are typically used to hold things together.

Since there is a lot of friction the ideal mechanical advantage doesn’t mean much. But in order to lift heavy items or when needing to hold things together, the screw is of great advantage. Equation = Circumference Pitch

Change in force A screw requires a small force when turning, in order to overcome a larger amount of resistance force.

For example, suppose a screw with 12 threads per inch is turned by a screwdriver having a handle with a diameter of 1 inch. The mechanical advantage would be calculated as follows: First, determine the pitch of the screw... Pitch = 1 = 1 = .083 12 threads/inch of screw 12 Second, determine the circumference of the handle of the screwdriver... Circumference = 3.14 x diameter = 3.14 x 1 = 3.14 inches Finally, insert the values obtained into the formula and solve the equation... Mechanical Advantage = Circumference = 3.14 inches = 37.83 Pitch .083

Pencil Sharpener Screw Incline Wedge

Bicycle Screw Wheel and Axle Pulley Lever

Cork Screw Screw Lever Wheel and Axle

Explained how my simple machine works. Allowed me to see how a screw can change forces. Gave different examples of what a screw is. Helped out when I needed to make up my own mechanical advantage problem. Provided good information explaining what a screw is

Simple Machines: WEDGE
Lisa Clay Period 12

What is a wedge and it’s advantage?
The wedge is the active twin of an inclined plane This simple machine consists of a pair of inclined planes set face-to-face, that can sustain relative sliding or rolling motion. Which makes it an advantage for a controlled and precise motion

How does a wedge change the force?
The purpose or advantage of the wedge is to change the direction of the applied force. When the force is applied downward on a wedge, it is able to push outward in two directions

Equation that shows mechanical advantage of a Wedge!
MA= L / W To solve the equation to find the mechanical advantage of a wedge you have to take the ratio to its length to the ratio of its width

MA=L / W MA=12/4 MA=3 12 4

Compound Machine #1- Boat
The wedge is located that the front of the boat, where the boat actually splits the water to let it glide. A pulley is also located in the boat which turns the wheels. Which makes a boat a compound machine.

Compound Machine #2- Fan
The blades in which cut the air as it spins is acting as a wedge There is a wheel and axel in which makes the fan spin. Which considers it a compound machine

Compound Machine #3- Shovel
The metal in which spits the ground as it shovels serves as the wedge The handle in which sticks out from the wedge serves as a lever which makes a shovel a compound machine

Websites Used http://www.weirdrichard.com/wedge.htm

Wheel and Axle By: Dakotah Kurtz

What is it? Well, the simple machine “Wheel and Axle,” consists of a large wheel, attached to a smaller wheel. Then, you can turn the smaller wheel, making the big wheel cover more distance. Or, if you turn the big wheel, it takes less force, but requires more motion.

Mechanical Advantage The mechanical advantage of a wheel and axle is equal to the rotation of the radius of the wheel to the radius of an axle. The equation for the mechanical advantage is the ratio of the size of the wheel to the size of the axle.

The wheel and axle changes the rate at which force is applied. If the force is applied to the axle, more force is required, but the distance traveled is greater. And vice – versa. M.A. = RadiusWheel/RadiusAxle As the small wheel turns, the big wheel turns at the same revolutions, but with the big wheel, that is a bigger distance. =]

Car The simple machines in a car are the wheel and axle, the levers, the pulleys, and probably more.

Fans! A fan is a complex machine that uses a wheel and axle. The axle is the small cylinder that comes down from the ceiling. The wheel are is made up of the blades Of the fan. It also uses a wedge to slice the air and pulleys in the motor.

Wheel Barrow! A wheel barrow is a complex machine that uses a wheel and axle. It also uses a lever when you lift the handle. The wheel then acts as a fulcrum.

Bibliography http://en.wikipedia.org/wiki/Wheelbarrow