Levers are inflexible, rigid bars that are used to do work. They are one of the six kinds of simple machines. Levers turn, or pivot, on a fulcrum. There are three different classes of levers.
Class Two Lever Examples
12 Best Levers images in | Simple machines, Physical Science, Physical Therapy
A lever could be something as simple as a wooden board with a ridge that freely rotates or moves on a pivot. The most common and popular lever can be found in many playgrounds: a see-saw or teeter-totter. They are found everywhere and it is one of the most useful simple machines. There are three classes of levers. All classes of levers have four basic parts: Beam- The lever, a wooden plank or metal bar resting on the fulcrum. Fulcrum- the pivot or the turning point. Force- the effort or input needed to move the beam and load.
Other classes of levers
The lever is one of the six simple machines which were defined by Renaissance scientists hundreds of years ago, also including the wheel , the inclined plane , the screw , the wedge and the pulley. You have used a lever in some shape or form without actually realizing it. So for instance scissors, nut crackers, pliers, hedge shears, bolt cutters and lopping shears all use levers in their design. A prybar or crowbar is a lever also, and when you prise open the lid of a tin with the handle of a spoon, you are using "the law of the lever" to create a greater force.
Types of lever: What kind of lever is a see-saw? All levers fall into one of three types of lever. How can we tell which lever is in which class?