Pulleys in Everyday Life

Post on 01-Jan-2016

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Pulleys in Everyday Life. Let’s look at some places we use pulleys. CONSTRUCTION. A crane uses a single pulley Uses gears to help move the crane around. MECHANIC. Uses pulley to lift heavy items out of cars. CAR ENGINE. - PowerPoint PPT Presentation

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Pulleys in Everyday Life

Let’s look at some places we use pulleys

CONSTRUCTION

• A crane uses a single pulley• Uses gears to helpmove the crane around

MECHANIC• Uses pulley to lift heavy items out of cars

CAR ENGINE• This is a serpentine belt that moves

around inside an engine to help a car move; it moves on pulleys

LOADING DOCKS• Machines similar to cranes help lift and

lower large shipping containers onto and off of ships

WELL• In many places where there is no water, they

use a well• Pulley is at the top and used to lift and lower

water bucket

GYM• Weight machines have visible pulleys to help lift

and lower the weights• Other machines like a treadmill or stationary bike

also use pulleys to allow the parts to move

CLOTHESLINE• Many people choose to hang their laundry to dry

instead of using a dryer• Pulley system allows them to hang clothes on

the line, and pull the rope along to get empty rope or collect the dry clothes

TOW TRUCK• Uses a pulley on the hitch to lift cars• Also needs gears and a motor to lift

CURTAINS

• Uses pulleys to open and close

ROCK CLIMBING• Uses pulleys to help

lift themselves up

steep rock faces

WINDOW WASHER• Uses pulleys to move up and down the sides of

building to wash windows• Painters also use these when painting areas out

of ladder reach

MOVIE PROJECTOR• This is an old one, but similar ones are still used

in movie theatres• Film passes over two large pulleys as light passes through the film to displaythe images that move together to make a movie

DRAWBRIDGES• Pulleys used to move cables, working with

gears and a motor, to lift a bridge

FLAGPOLE• Uses pulleys to lift and lower flags

ELEVATORS• Pulleys used to allows metal cable to move elevator up and down with the help of a counterweight and a motor

SAILS• Boats with sails need pulleys to lift the

sails and to move them around

FISHING • Fishermen who fish commercially use large nets that are brought in using a pulley

• Pulleys are used in many ways all around us!• Without them, some tasks would be much more

difficult or could not happen at all!• Pulleys allows lifting, lowering, and some

movement to be made easier• Pulleys must be strong and not produce too

much friction for the cables passing over them• Pulleys can be fixed (attached to something) or

not• Combining pulleys requires less force (more

pulleys = less work)