Movable pulleys are used frequently and some common examples include weightlifting machines used in modern gyms, construction cranes and elevators. Many are used in very large and complex pieces of industrial machinery, while others are simple portable devices like chain or mining hoists.
All pulleys are simple mechanical devices that have been in use for many centuries, and historians believe humans were using simple static pulleys as far back as 1500 B.C.
There are several examples of movable pulleys that appear frequently in everyday life including:
Levers and pulleys are two types of simple machines that allow people to use less energy when performing work. A simple lever is a long pole or platform used to lift an object. In a simple pulley system, a rope looped around a wheel is used to raise and lower objects.Full Answer >
A movable pulley is a pulley that can freely move. This is only one of three types, the other two being fixed and compound pulleys. Examples of movable pulleys are elevators.Full Answer >
Elevators use pulleys as they move the passenger compartments up and down from one floor to the next. Drapery and window blinds also use pulleys -- much smaller than the ones for elevators -- to move the blinds or drapes around.Full Answer >
A pulley works by changing the direction that force must be applied to lift an object against gravity. Other, more complex, systems use multiple pulleys to reduce the amount of force that must be applied.Full Answer >