Question 15 MarksHow does a pulley make work simpler ? Differentiate between a single fixed pulley and a single movable pulley.AnswerA pulley is a wheel or a circular disc that can rotate freely about its axle. It is used to lift Heavy objects. It is neither a force multiplier nor a speed multiplier. It only changes the direction of the applied force from upwards against gravity to downwards towards gravity. There are two types of pulley systems – Single fixed pulley and single movable pulley.Single fixed pulley:This pulley has a fixed axis of rotation.The load is attached to one end of the rope.Only the direction of the force is changed, not the magnitude, [We can lift the object higher but heaviness of load remains the same]The mechanical advantage of this pulley is 1.Example : Used to draw water from wells.Single movable pulley :The axis of rotation of this pulley is not fixed.The load is attached to the pulley.The direction of the force as well as the magnitude of force change.The mechanical advantage of of this pulley is 2.Example : Used in construction cranes, weight lifting, machines in gym, etc.View full question & answer→
