The orbital motions of planets and comets, as depicted here, are governed by the laws of mechanics.
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Windows to the Universe original artwork by Randy Russell.


Mechanics is one of the main branches of physics. Mechanics deals with the motion of physical objects. It also deals with the forces that act on physical objects. How hard do I have to pull a full wagon before it will budge? What happens when an asteroid slams into a planet? How should we launch a satellite to put it into orbit? These are the sorts of questions that the study of mechanics can help us answer.

You may have studied mechanics without knowing it. Have you ever studied or built a simple machine like a lever or pulley? Those machines that make our work easier use the laws of mechanics to work.

Last modified September 12, 2008 by Randy Russell.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA