Simple Machines: lever, pulley, wheel and axle and incline

Group LL

The Lever

By Sean Rzeplinski

Type one lever

• This type of lever is a pivot point in the middle of a beam where there is a load on one side and an effort on the other. With this type of lever you can lift a larger load with less effort, but it is only moved a small distance.

Type two lever

• This type of lever has the pivot on the end with the load in between the pivot and the effort. With this type of lever you can still move a larger load with less effort

Type three lever

• This type of lever has the pivot on the end with the effort in the middle and the load on the other end. This type of lever has the effort greater than the load.

PulleysPulleys

Pictures of PulleysPictures of Pulleys

What is a Pulley?What is a Pulley? A A pulleypulley is a mechanism composed of a wheel with a is a mechanism composed of a wheel with a

groove between two flanges around the wheel’s groove between two flanges around the wheel’s circumference. circumference.

A rope, cable or belt usually runs inside the groove. A rope, cable or belt usually runs inside the groove. Pulleys are used to Pulleys are used to

change the direction of an applied forcechange the direction of an applied force Transmit rotational motionTransmit rotational motion Realize a mechanical advantage in either a linear or rotational Realize a mechanical advantage in either a linear or rotational

system of motionsystem of motion

Equations:Equations: Necessary Force:Necessary Force:

If there are 4 pulleys with a weight of 14 N,the If there are 4 pulleys with a weight of 14 N,the weight is 2.0 Nweight is 2.0 N

F= (14.o N + 2.0 N) :4F= (14.o N + 2.0 N) :4= 4.00 N= 4.00 N

Compound MachineCompound Machine

Different Machines:

•Pulleys

•Incline

•Wheel and axle

Compound Machine #2 Compound Machine #2

Other Machines:Other Machines: PulleysPulleys InclineIncline Wheel and AxleWheel and Axle

BibliographyBibliography http://library.thinkquest.org/27948/pulley.hhttp://library.thinkquest.org/27948/pulley.h

tmltml http://http://en.wikipedia.orgen.wikipedia.org/wiki/Pulley/wiki/Pulley

Wheel & Axle

By Olubode Afuape

Wheel & Axle

Wheel & Axle is a simple machine.This form of a simple machine consists of a wheel that

turns an axle and while it turns the wheel, a rope or string converts the rotational motion to linear motion for the purpose of moving, or lifting.

All wheels need an axle to function. The wheel and axle

must move together for it to become a simple machine.

Wheel

Ideal Mechanical Advantage

• What is the ideal mechanical advantage?• Ideal mechanical advantage is the ratio of the radius of

the wheel to the radius of the axle.• An example would be in the picture below the, the radius

of the wheel is five times larger than the radius of the axle. Therefore, the mechanical advantage is 5:1 or 5.

Change the ForceEvery simple machine changes the amount of force

needed. In Wheel & axle, less energy is used to change the force, this is because the object is already rolling, allowing it to have less friction and be easier to move then when static.

Compound Machine

List of Simple machinesPulleyWheel & Axle

List of Simple MachinesWheel & AxleScrewPulleyLever

List of Simple MachinesWheel & AxlePulleyScrewLever

Bibliography• *http://en.wikipedia.org/wiki/Wheel_and_axle*• *http://classroom.jc-schools.net/coleytech/units/machines/Wheels_and_Axles.ppt#271,5,Slide

5*• *http://www.usoe.k12.ut.us/curr/Science/sciber00/8th/machines/sciber/machine7.htm*• http://www.worsleyschool.net/science/files/wheel/andaxle.html• http://www.fi.edu/pieces/knox/automaton/wheel.htm

Help info• Wheel and axle notion (e.g. screwdrivers,

doorknobs): A wheel is essentially a lever with one arm the distance between the axle and the outer point of the wheel, and the other the radius of the axle. Typically this is a fairly large difference, leading to a proportionately large mechanical advantage. This allows even simple wheels with wooden axles running in wooden blocks to still turn freely, because their friction is overwhelmed by the rotational force of the wheel multiplied by the mechanical advantage.

InclineIncline

By moving an object up an inclined plane By moving an object up an inclined plane rather than completely vertical, the amount rather than completely vertical, the amount of force required is reduced, at the same of force required is reduced, at the same time increasing the distance the object time increasing the distance the object has to travel.has to travel.Example: Roman soldiers built an inclined Example: Roman soldiers built an inclined plane out of earth and clay to lay siege to plane out of earth and clay to lay siege to the Masada in 73 b.c.the Masada in 73 b.c.

““Inclined Plane”Inclined Plane”

An incline plane is a plane surface that is An incline plane is a plane surface that is set at an angle, other than a right angle, set at an angle, other than a right angle, against a horizontal surface.against a horizontal surface.Examples of inclines are ramps, sloping Examples of inclines are ramps, sloping roads, chisels, hatchets, plows, air roads, chisels, hatchets, plows, air hammers. hammers. Another common name for the incline is a Another common name for the incline is a ramp. ramp.

ForceForce

The normal force is exerted by the plane The normal force is exerted by the plane onto the body. (N)onto the body. (N)The force due to the gravity acts vertically The force due to the gravity acts vertically downward (mg)downward (mg)And the frictional force acts parallel to the And the frictional force acts parallel to the plane (F)plane (F)

TreadmillTreadmill

Roller CoastersRoller Coasters

http://en.wikipedia.org/wiki/Inclined_planehttp://en.wikipedia.org/wiki/Inclined_planehttp://www.ac.wwu.edu/~vawter/PhysicsNhttp://www.ac.wwu.edu/~vawter/PhysicsNet/Topics/Dynamics/InclinePlanePhys.htmlet/Topics/Dynamics/InclinePlanePhys.htmlhttp://www.inclinedplane.com/http://www.inclinedplane.com/