What is a water wheel? Many people ask about what a water wheel is used for and by the end of this essay they will be knowing more about this topic. The water wheels were invented in late 1870 's. The chinese of the Eastern Han Dynasty used water wheels to crush grain in mills or power the piston-bellows in forging iron into cast iron("Waterwheel"). Waterwheels of ancient China had a positive impact on the society 's balance of power, while impacting the economy in different ways, the environment was impacted very badly. A water wheel in Ancient China was used to crush grains or to cast iron. It was first invented by Nikola Tesla. A water wheel is a machine for converting the energy of falling water into some forms of power ("Wikipedia"). A water wheel consists of a large piece of wood with a few buckets arranged on the outside rim forming the driving surface ("wikipedia"). The energy changes are water energy of water to kinetic of water wheel to electricity of the generator/motor. This was just a small information about the water wheel. The water wheel effected the environment very badly in the old times. To make a water wheel there needs to have wood and wood comes from trees. So, the trees are part of the environment, if there are more water wheels, there would be less trees. If they cut down most of the trees, there would be less oxygen and some people with respiratory problem or difficulty with breathing could be seriously injured if they cut down most trees in