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 in Physics
A class 2 lever is a lever with the fulcrum or joint at one end, with the load that is being carried in the middle. The effort, which is the object lifting or pulling the lever, is at the opposite end from the fulcrum.Full Answer >
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 >
The upper second-class honours degree is a classification in the United Kingdom's university undergraduate degree structure. Degrees are awarded with or without honours, thereby distinguishing the achievements of graduates. Almost all graduates sit for honours and the majority of these graduates fall into either the upper or lower second-class divisions.Full Answer >
The cost to mail a letter second class in the United Kingdom starts at 53 pence depending on its size and weight, and at 81 pence for international. Postage for parcels mailed second class starts at Â£2.80 for small packages and can go up to Â£28.50 for medium-size packages.Full Answer >