| A | B |
| electromagnetic waves | a form of energy that can travel through space. |
| radiation | the direct transfer of energy through empty space by elelectromagnetic waves. |
| infrared radiation | a form of energy with wavelengths that are longer than visible light. |
| ultraviolet radiation | a form of energy with wavelengths that are shorter than visible light. |
| scattering | reflection of light in all directions. |
| thermal energy | the energy of motion in the molecules of a substance. |
| thermometer | an instument used to measure temperature. |
| conduction | the transfer of heat from one substance to another by direct contact. |
| temperature | the average amount of energy of motion in the molecules of a substance. |
| heat | the energy transferred from a hotter object to a cooler one. |
| convection | the transfer of heat by movements of a fluid. |