Half of the Earth's crust and most of your body is made of oxygen. Fossils are found embedded in rocks or in other materials that form the earth's crust. Coal, gas, oil and wood are fuels. A machine that changes the power or energy from a natural source, such as water or wind, into electricity. A hurricane is a severe storm.
Hurricanes form over oceans near the equator, where the air is very moist.
The center of a hurricane is a narrow column of air that spins very slowly. The tiny nucleus at the center of the atom contains the most powerful force ever discovered. This force gives us nuclear energy, sometimes called atomic energy. The most complicated element that occurs in nature is uranium. The nuclear fuel used in nuclear power plants is a rare form of uranium called uranium-235.