Question

if the center circle of pulley is enlarged, how does it effect the force output? please give detailed answer

Answer 1

The friction in between the string and pulley is increased and it will give less output.

Answer 2

A pulley system makes it easier to lift an object than lifting the dead weight by hand. A single pulley essentially changes the direction of the pull or force applied. When a person uses two or more pulleys in a system, then the system also multiplies the force applied besides changing its direction. With one fixed and one movable pulley in a system, it essentially doubles the weight of the load you could lift without help from another person based upon the weight you can lift.