Question

why is a Single movable pulley never used alone

Answer 1

Answer:

HOPE IT HELPS.....

Explanation:

The movable pulley reduces the effort required to pull a mass by factor of 2 × number of movable pulleys. Consider a simple example of single fixed and movable pulley.

In case I of fixed pulley the effort will be same as of load being lifted as tension in rope will be same across pulley, hence mechanical advantage will be 1.

Feffort=Fload

In case II of movable pulley the effort will be half of that load being lifted as the forces on mass less pulley should balance, mechanical advantage will be 2.

2Feffort=Fload⇒Feffort=Fload/2

Movable pulley is used as force multiplier, correct answer is option A.