Landfills are used for the disposal of solid waste. Reduce, Reuse, and Recycle are ways to reduce waste. People of different races, cultures and genders have contributed to our environmental awareness. The lever, inclined plane, pulley, wedge, gear and wheel and axle, are simple machines. Force can be measured.
Simple machines can reduce the force needed to perform work.
Simple machines can be evaluated by comparing measurements of force. Simple machines can be combined in different ways to create new complex machines. Simple machines are used in many tasks and occupations. Rocks can be classified as metamorphic, sedimentary or igneous. Metamorphic rocks are formed in the earth's crust by pressure and heat.