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.Know More
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
First-class proteins are proteins found from animals, and second-class proteins are proteins found from plants. First-class proteins come from meat, eggs, fish and dairy products while non-animal related foods, like vegetables and fruits, provide second-class proteins.Full Answer >
A free-falling object increases its speed by 9.81 meters per second each second. The force of gravity is the same for all objects; however, air resistance starts to become a factor as the speed increases.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 >
According to the Royal Mail Group, second-class stamp prices vary depending on their purpose. As of July 2014, a second-class stamp for a letter is 53 pence, and second-class postage for a large letter starts at 73 pence, small parcels start at ?2.80 and medium parcels start at ?5.20.Full Answer >