What is pully definition?

A pulley is a simple machine consisting of a grooved wheel or drums that rotate on an axle and a rope or cable that passes over the groove of the wheel. The rope or cable can be pulled to lift and move heavy objects. Pulleys are commonly used in cranes, elevators, and other lifting devices to reduce the amount of force required to lift heavy objects. The two types of pulleys are fixed and movable pulleys. Fixed pulleys are attached to a stationary point and do not move, while movable pulleys are attached to a moving object and move along with it. Pulleys are useful for mechanical advantage, making it easier to lift or pull objects with less force.