Question

In a single movable pulley,
(A). Ideal mechanical advantage is 1
(B). Load moves in the direction of effort
(C). Velocity ratio is 1
(D) .All

Answer 1

Hint: Try to learn about simple machines. Try to understand the concept about how different pulleys’ work. Understand the definitions of the terms in the questions and try to find out these quantities for single movable pulleys.

Complete step by step answer:
Pulleys are one of the six simple machines. A pulley is a tool made of wheel and rope to perform mechanical work, mostly lifting an object upward or moving the object downward.
In a movable pulley system, we attach the one end of the rope to a wall or ceiling and the object is put on the pulley which is movable on the rope. This allows the pulley to move along the rope. Advantage of a movable pulley is that we need to do less work or we need to apply less force to do more work.
In a single movable pulley, the one end of the rope is fixed and the pulley is movable.
The input force is what force we apply to the machine and the output force is the force applied by a machine. Mechanical advantage can be defined as the ratio of the output force to the input force.
Ideal mechanical advantage means the mechanical advantage without friction. For a single movable pulley, the ideal mechanical advantage is 2, i.e. if we need a force of 100N to do a work, in a single movable pulley system we need only 50N or half the force to do the same work.
Again, single movable pulley does not change the direction of force. If we put a force in upward direction the machine will also have a force in the upward direction. So, in a single movable pulley the load moves in the direction of effort.
The velocity ratio can be found out as the ratio of the distance pulled by effort to the distance the object moves upward. For a single movable pulley, the velocity ratio is 2.
So, the correct option is (B).

Note: For a fixed pulley we have low mechanical advantage. For the movable or compound pulleys the mechanical advantage is more. In a compound pulley we have two or more than two pulleys to make the work easy.
With the increase in the mechanical advantage we need to put less effort or force to do the same work with pulleys.