Levers may not seem like much, however, they are among the most commonly used items around. Levers are everywhere, and it’s not a new thing at all. Levers have been who knows when. Even Archimedes of ancient Greece said “Give me a lever long enough and I can lift the world”.

Levers may not be that powerful but they sure do make heavy lifting one heck of a lot easier. That’s not all levers can do though, for instance a car relies almost entirely on spinning levers, also known as gears. This video will show you all about that though.


Levers have also been used many times in weapons. One classic example is the catapult.

So the uses of levers are never ending so

          How do levers work?

For starters, the dictionary defines the lever as a rigid bar used for leverage.

But before we even begin learning about how levers work we should know about a few basic items.

1. The Fulcrum.
A fulcrum something that supports something else that relies on only the fulcrum to hold itself up. In the case of levers that something is a lever.

2.The Load.
The load is what you are trying to lift or balance. The load is sometimes referred to as the resistance force or just resistance

3.The Force
The force or effort is basically the force or weight you are using to lift or balance out the load.

There are three different classes of levers.

(Class one, two, and three levers in that order.)
In a first class lever of  the fulcrum is underneath the middle of the lever. The force is on one side and the load is on the other. A good example of a class one lever is a balance scale.

In a class two lever the load is put on the middle of the lever, the force is put on either side, and the fulcrum is put on the opposite side of the load. A good example of a second class lever is a nutcracker.

In a class three lever the force is applied to the middle of the lever, the fulcrum is on one side of the lever, and the load is on the other side of that. A good example of a class three lever is a claw hammer.

One cool example of a class one lever is a trebuchet. A trebuchet is a medieval siege weapon that uses a very basic lever to throw huge projectiles at an enemy. In a trebuchet the fulcrum is positioned very close to the effort which is a much heavier weight. The load is hung on the other side of the lever. When the very heavy counterweight or effort is quickly applied to the other side of the much lighter load the load goes flying.
To see what a trebuchet was like have fun playing around with it by crushing medieval castles and people here :
 To learn more about levers you can visit World-Star Academy's lever post here :Levers-World Star Academy

Did you learn anything? Please tell me if I did a good or bad job by commenting. If I did a bad job please tell me how I can improve this post.



No comments:

Post a Comment

Speak your mind! Please Comment!