Date post: | 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 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)