Question

The mechanical advantage of a lever is equal to:

Answer 1

Hint: The lever is a kind of simple device used to reduce effort. Normal lifting of weight and lifting with the fulcrum will be different as we will need less load in the latter case.
The lever while lifting gets divided into two arms from fulcrum to load and from fulcrum to lifter.

Complete answer:
As we know, a lever is a simple mechanical device. We can use it to lift the load.
If one end of the lever is pushed down, the force will lift the other end. If the other end has a load on top of it, it will be easier to move the load. The lever makes the work easier.
Generally, the load will not be possible to lift using the normal strength of human beings. For that a fulcrum is made in between the load and lifter.
This helps in determining the distances for the execution of the same task i.e. lifting the load,
Now, the arm from fulcrum point to load and fulcrum point to the lifter is termed with the names, ‘load arm’ and ‘effort arm’.
Load arm is the distance between load to the fulcrum and Effort arm is the distance between fulcrum and the lifter.
The ease with which the task is being done is a mechanical advantage of lever. This mechanical advantage is the ratio of Effort arm to the load arm.
$ Mechanical\,Advantage = \dfrac{{Effort\,arm}}{{Load\,Arm}}$
This is also known as the principle of lever.

Note: There are three different classes of levers. The class of lever depends on the location of the load, force, and fulcrum. Some examples of levers include more than one class, such as a nutcracker, a stapler, nail clippers, ice tongs and tweezers.