| A | B |
|---|
| crust | outermost layer of Earth |
| mantle | movement of tectonic plates |
| seismic waves | how scientists studied Earth's layers |
| fault | break in Earth's crust |
| Newton's 1st Law | an object at rest stays at rest |
| Newton's 2nd Law | net force of an object = to product of its mass and acceleration |
| Newton's 3rd Law | for every action force there is an equal opposite reaction force |
| atmosphere | mixture of gases that is a thin shell surrounding Earth |
| altitude | height above sea level |
| air pressure | force that is the result of the weight of a column of air pushing down on an area |
| condensation | process by which molecules of water vapor in the air in the air become liquid water |
| troposphere | all weather occurs here |
| stratosphere | ozone layer |
| mesosphere | meteors burn up here |
| thermosphere | contains ionosphere and exosphere |
| speed | distance divided by time |
