A lever is simply a rigid beam that can rotate freely on a pivot. It is perfect for moving heavy objects. It is a simple and very useful machine. A lever is simply a rigid beam that can rotate freely on a pivot. It is perfect for moving heavy objects. It's a simple and very useful machine, and you can find them everywhere. Good examples of levers include the swing, crowbar, fishing line, oars, wheelbarrows, and garden shovel. A lever is simply a rigid board or beam free to rotate on a pivot. It is perfect for lifting or moving heavy objects. It's a simple and very useful machine, and you can find them everywhere. Good examples of levers include the swing, crowbar, fishing line, oars, wheelbarrows, and garden shovel. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get the original essayA lever is a simple machine consisting of a long beam that is attached to a pivot point (fulcrum) on a load that is attached and an effort force is applied. Levers work to reduce the amount of effort needed to move a load, thereby providing a mechanical advantage. Longer levers provide a much greater mechanical advantage. A lever is a machine that makes work easier. It involves moving a load around a pivot using force. Simply put, levers are machines used to increase strength. We call them “simple machines” because they only have two parts, the handle and the fulcrum. The handle of the lever is called the “arm,” which is the part that you push or pull on. The “fulcrum” is the point on which the lever rotates or balances. In the case of a fork, the fulcrum is the fingers of your hand. The scissors are actually two levers joined together. The toilet flush handle is commonly called a fixed lever. Take a quick look around and see how many levers you can find. It is perfect for lifting or moving large and heavy objects. It's a simple machine and you can find them anyone. Good examples of levers include the crowbar, swing, fishing line, oars, wheelbarrows, and garden shovel. Levers are among the common tools probably used in prehistoric times. Levers were first discovered around 260 BC by the Greek mathematician Archimedes. The axis of the levers is off-center between the work of the load and the lever. The largest load of effort is moved a small distance. Catapults have been an integral part of siege warfare since ancient times. Ancient catapults were one of the most effective weapons in siege warfare. Different types of catapults were used by the Greeks, Romans and Chinese. Early catapults were early attempts to increase the range/power of a crossbow. Diodorus Siculus, a Greek historian, was the first to document the use of a mechanical catapult firing arrows (early ballista) in 399 BC. Catapults as we consider them were introduced to Europe in the Middle Ages. The catapults were exhibited in England in 1216 during the siege of Dover, the French crossed the Channel and were the first to use the catapults on English soil. With warfare raging across Europe in the Middle Ages, the popularity of fortified castles and city walls increased significantly. This made catapults an essential item. Keep in mind: this is not..