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10.26.2011Take out your notebook Write todays dateThe 6 Simple Machines

LeverPulleyWheel and AxleWedgeScrewInclined Plane

Fulcrum is between EF (effort) and RF (load)Effort moves farther than Resistance. Multiplies EF and changes its direction

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.

Lever

First Class LeverFirst Class Lever. Common examples of first-class levers include crowbars, scissors, pliers, tin snips and seesaws.

RF (load) is between fulcrum and EF Effort moves farther than Resistance. Multiplies EF, but does not change its direction The mechanical advantage of a lever is the ratio of the distance from the applied force to the fulcrum to the distance from the resistance force to the fulcrum.

Second Class LeverSecond Class LeverExamples of second-class levers include nut crackers, wheel barrows, doors, and bottle openers.

EF is between fulcrum and RF (load) Does not multiply force Resistance moves farther than Effort. Multiplies the distance the effort force travels The mechanical advantage of a lever is the ratio of the distance from the applied force to the fulcrum to the distance of the resistance force to the fulcrum

Third Class LeverThird Class LeverExamples of third-class levers include tweezers, arm hammers, and shovels.

2. PulleysPulley are wheels and axles with a groove around the outsideA pulley needs a rope, chain or belt around the groove to make it do work

Diagrams of PulleysFixed pulley:

A fixed pulley changes the direction of a force; however, it does not create a mechanical advantage. Movable Pulley:

The mechanical advantage of a moveable pulley is equal to the number of ropes that support the moveable pulley. COMBINED PULLEYThe effort needed to lift the load is less than half the weight of the load. The main disadvantage is it travels a very long distance.

3. Inclined PlanesAn inclined plane is a flat surface that is higher on one endInclined planes make the work of moving things easier

12A sloping surface, such as a ramp. An inclined plane can be used to alter the effort and distance involved in doing work, such as lifting loads. The trade-off is that an object must be moved a longer distance than if it was lifted straight up, but less force is needed.You can use this machine to move an object to a lower or higher place. Inclined planes make the work of moving things easier. You would need less energy and force to move objects with an inclined plane.

Inclined Plane

Inclined PlaneThe Egyptians used simple machines to build the pyramids. One method was to build a very long incline out of dirt that rose upward to the top of the pyramid very gently. The blocks of stone were placed on large logs (another type of simple machine - the wheel and axle) and pushed slowly up the long, gentle inclined plane to the top of the pyramid.

4. Screw

5. WedgesTwo inclined planes joined back to back. Wedges are used to split things.

W e d g e A wedge is a piece of hard material with two principal faces meeting in a sharply acute angle, for raising, holding, or splitting objects by applying a pounding or driving force, as from a hammer. Wedges can be used as either separating or holding devices.

Wheel and axle is an example of a simple machine, that has two parts to it.

Unlike most simple machines, the parts have to work together, in order to move it.

Wheel and axle machines, have the axle attached to the wheel, to help it to move, and to speed up things. 6. Wheel and AxleWhat makes it a wheel and axle system?The wheel must be fixed to the axle.One rotation of the wheel equals one rotation of the axle.If the wheel and axle are not fixed then you basically have a pulley system.19Everyday examples of a wheel and axle systemA doorknobFishing reelCarousel20Find the wheel and axles

21Rube Goldberg Machines

Rube Goldberg machines are examples of complex machines.All complex machines are made up of combinations of simple machines.Rube Goldberg machines are usually a complicated combination of simple machines.By studying the components of Rube Goldberg machines, we learn more about simple machines

When you slip on ice, your foot kicks paddle (A), lowering finger (B), snapping turtle (C) extends neck to bite finger, opening ice tongs (D) and dropping pillow (E), thus allowing you to fall on something soft. Safety Device for Walking on Icy Pavements Examples of Simple machines and Compound machines10.27.2011Take out your notebook and write todays dateClasses of LeversFirst Class Lever

Examples:SeesawScissors (double lever)

Classes of Levers

Second Class LeverExamples:WheelbarrowNutcracker

Classes of LeversThird Class LeverExamples:Hockey StickTweezersFishing Rod

Where can I find them?Compound machine:Can Opener

Simple machines- lever-wheel and axle-wedge

Where can I find them?Compound Machine:Wheelbarrow

Simple Machines:-Lever-Inclined Plane-Wheel and Axle

A Wedge in a Compound Machine: Scissors The cutting edge of scissors is a wedge.

Simple machines in a pair of scissors:WedgeLever

pencil sharpener1Casters2door knobs3rolling pIn4rotary dial telephone5egg beater6Bicycle7Fan8Windmill9 roller skates 10record player11Wagon12

Well that uses the wheel and axle method.

A skate board is an example of a simple machine that uses the wheel and axle method.

A wheel Barrel is a compound Machine Wheel and axle simple machine lever simple machine.

A Car uses the wheel and axle method for the steering wheel and the axle, or other wise known as the Dry Shift. It also uses lever for things like the gas/brake pedals, and emergency brake. Screws are found anywhere in the interior and the hood, and car also have pulleys in the engine drive belt, for the water pump, and the alternator. Compound Machine #1Bow flex: Pulley lifts the weight, the seat is an inclined plane, and the lever is what you pull to adjust the seat

Compound Machine #2Crane: The lever is the horizontal beam that lifts the object, the pulley is used to make the rope tight so that it is easier for the crane to lift the object

Compound Machine #3Ski Lift: It is an inclined plane to travel up a mountain. The pulley is used to pull the ski lift to the top of the mountain.