According to Ohio University, there are three main classes of levers. These are distinguished by the relative locations of the load, effort and fulcrum along the lever. A second-class lever is one in which the load, or the item being lifted, is found between the effort and the fulcrum, or pivot point.Continue Reading
First-class levers are those which have the fulcrum placed between the load and the effort. Examples of first-class levers are the seesaw and crowbar. On a seesaw, for example, the person on the higher end of the plank acts as the effort, applying a downward force to the end of the lever. The person on the other end is the load, and the point at which the plank pivots is the fulcrum.
Ohio University lists the wheelbarrow as an example of a second-class lever. The effort is applied to the handles, the axle of the wheel acts as the fulcrum or pivot point, and the load is found in the middle.
Third-class levers are those in which the load and fulcrum are located at opposite ends of the lever with the load placed between them. An example of this class of lever is the hammer. When used to pound a nail into a board, the user's wrist is the fulcrum, the point at which the hand contacts the hammer is the effort, and the resistance of the wood to pounding is the load.Learn more about Physics
A lever is a simple machine, and it only consists of two material components and two work components. A lever can be made with a beam, or solid rod; a fulcrum, or pivot point; an input force, or effort; and an output force, or load or resistance.Full Answer >
A baseball bat is a third-class lever, with the fulcrum at the end, the force located in the center and the load the point where the ball strikes. Third-class levers require more work to accomplish the job but give the mechanical advantage moving with increased speed.Full Answer >
The axle and wheel, a wedge, an inclined plane, a lever and a pulley, as well as a screw, are six simple machines that kids can make for a physics lesson. The machines, which can be constucted from simple household items, demonstrate all of the founding principles of physics.Full Answer >
A fulcrum is the fixed support or pivot point for a lever, which is a simple machine used to overcome resistance. The lever is a stiff rod or bar, and the location of the fulcrum determines the class of the lever. Levers are useful to increase force, increase speed or change direction of a force, according to HowStuffWorks.Full Answer >