A lever is simply rigid beam that is free to rotate on a pivot. It is perfect for moving heavy things. It is a very useful simple machine. A lever is simply rigid beam that is free to rotate on a pivot. It is perfect for moving heavy things. It is a very useful simple machine, and you can find them everywhere. Good examples of levers include the seesaw, crowbar, fishing-line, oars, wheelbarrows and the garden shovel. A lever is simply a plank or rigid beam that is free to rotate on a pivot. It is perfect for lifting or moving heavy things. It is a very useful simple machine, and you can find them everywhere. Good examples of levers include the seesaw, crowbar, fishing-line, oars, wheelbarrows and the garden shovel.
A lever is a simple machine comprised of a long beam that is fixed to a pivot point (fulcrum) onto a load is attached and an effort force is applied.
Levers work to reduce the amount of effort required to move a load, providing a mechanical advantage. Longer levers provide a much greater mechanical advantage. A lever is a machine that makes work easier for use it involves moving a cargo around a pivot using a force. Simply put, levers are machines used to increase force. We call them “simple machines” because they have only 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 turns or balances. In the case of a fork, the fulcrum is the fingers of your hand. Scissors are really two levers put together. The handle on the toilet flusher is commonly called a fixed lever. Take a quick look around you and see how many levers you can find. It is perfect for lifting or moving big and heavy things. It is a simple machine, and you can find them anyone. Good examples of levers include the crowbar, seesaw, fishing-line, oars, wheelbarrows and the garden shovel. Levers are one of the ordinary tools that were probably used in prehistoric times. Levers were first discovered about 260 B.C. by the Greek mathematician Archimedes. The levers axle is in between the work of the load off-center of the lever. The larger cargo of the effort is moved through a little distance. Catapults have been integral to siege warfare since antiquity. The ancient Catapults were one of the most effective weapons in siege warfare.
Different types of Catapults have been used by the Greeks, Romans, and Chinese. The first catapults were early attempts to increase the range/power of a crossbow. Diodorus Siculus, a Greek historian, was the first to document about the use of a mechanical arrow firing catapult (early Ballista) in 399 BC.
Catapults as we think of them were introduced to Europe during the Middle Ages. Catapults made their exhibition in England in 1216 during the Siege of Dover, the French crossed the Channel and were the first to use Catapults on English soil. With war prevalent throughout Europe during the Middle Ages the popularity of fortified castle and city wall rose significantly. This made Catapults an essential.
Catapults were used to launch missiles (many different objects were utilized). These missiles were either launched directly at the wall to cause maximum damage to the fortifications or were launched over the wall to lay siege on the population within the protective walls. Catapults were used to throw missiles at warriors. The first accounted acts of Biological Warfare involved catapults. Bodies of the diseased were thrown over the city walls to infect the residing citizens. Catapults were used vastly throughout Europe (mainly by the French) until 885-886 AD when new defense systems rendered catapults were ineffective.