By Jonathan Lemmon and Brook Dreher. Definition of Pulley a wheel with a grooved rim for carrying a...
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Transcript of By Jonathan Lemmon and Brook Dreher. Definition of Pulley a wheel with a grooved rim for carrying a...
PULLEY
By Jonathan Lemmon and Brook Dreher
Definition of Pulley
a wheel with a grooved rim for carrying a line, that turns in a frame or block and serves to change the direction of or to transmit force, as when one end of the line is pulled to raise a weight at the other end
How does it work?
A pulley is also called a sheave or a drum and is a mechanism made up of a wheel on an axle or shaft that may have a groove between two flanges around its boundary.
A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present.
Pulleys are used to change the direction of an applied force, or realize a mechanical advantage in either a linear or rotational system of motion
It looks like this
Uses
The pulley is used to move heavy objects by splitting the weight being pulled. Like a crane, it lifts up objects easily by using hydraulics in the arm so it is able to pull objects
How do you calculate IMA for the pulley Efficiency=AMA/IMA x 100%
AMA=Fr /Fe
Other info on pulleys
The pulley you turn causes the other pulley to turn also, because they are connected by a belt. The driver and the follower turn in the same direction.
Reference
http://www.eng.iastate.edu/twt/Courses/Undergrad/packet/info/pulleys.htm
The book http://en.wikipedia.org/wiki/Pulley