When a dam is placed in a river, water builds up on one side of the dam. an opening can be made in the dam, and a water wheel placed in that opening. as the water flows over the water wheel, energy is released that can be used to do work. the water wheel in the river is a good analogy for

Energy generation using renewable energy source

Explanation:

When a dam is placed in a river, water builds up on one side of the dam. An opening can be made in the dam, and a water wheel placed in that opening. As the water flows over the water wheel, energy is released that can be used to do work. The water wheel in the river is a good analogy for energy generation using a renewable energy source.

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.