| A | B |
|---|
| freefall | The condition of a falling object which experiences no friction and gravity is the only force acting on the object. A freefalling object always accelerates at the same rate and all objects in freefall accelerate at the same rate as each other. The rate of acceleration is 9.8 m/s2 downward near the surface of the earth. |
| gravity | a force field produced by an object's mass, which attracts other masses. Used to define down here on earth |
| precision | The degree of exactness with which an operation is performed or a measurement stated. |
| accuracy | Freedom from mistake or error; degree of conformity of a measure to a standard or a true value |
| independent variable | The factor in an experiment that the researcher chooses to vary at specific intervals; is plotted on the x-axis. |
| dependent variable | The factor whose value changes as the result of a change in the independent variable and is plotted on the y-axis. |
| slope | Refers to the degree of inclination or steepness of a line on a graph. Determined by dividing the rise by the run of the line. |
| model | A simplified description of a physical system intended to capture the essential aspects of the system in a sufficiently simple form. A description or analogy used to help visualize something (as an atom) that cannot be directly observed |
| hypothesis | An assumption to be tested; a statement of a problem to be solved, expressed as a question. |
| theory | A plausible or scientifically acceptable general principle or body of principles offered to explain phenomena |
| unit | A specific measure of quantity (length, time, heat, etc.) used as a standard of measurement. |
| observation | An act of recognizing and noting a fact or occurrence; often involving measurement with instruments. |
| experiment | An operation carried out under controlled conditions in order to discover an unknown effect or law, to test or establish a hypothesis, or to illustrate a known law. |
| law | A statement of an order or relation of phenomena that so far as is known is invariable under the given conditions. |
| standard | Set up and established by authority as a rule for the measure of quantity, weight, extent, value, or quality. |
