Create an account
any push or pull that makes an object start moving, stop moving, speed up, slow down, or change direction
the tendency of an object to remain in motion or stay at rest unless acted upon by an outside force
a machine with few moving parts, making it easier to do work; the six types of simple machines are the lever, pulley, wheel an axle, inclined plane, wedge, and screw
the measure of how much useful work a machine puts out compared to the amount of work put into it
the transfer of energy by the flow of liquids or gases, such as water boiling in a pot or warm air rising in a room
a substance such as coal or oil that was formed millions of years ago from the remains of plants and animals; these fuels are nonrenewable resources, and, when burned for energy, are a major source of pollution
an area of bunched-up and spread-out air particles that moves outward in all directions from a vibrating object
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together