| A | B |
|---|
| wavelength | the distance between a point on a wave and the same point on the next wave |
| reflection | bouncing back of waves upon reaching another surface |
| pitch | the property of sound that depends on frequency and determines how high or low a sound is |
| acoustics | the science of sound and its interactions |
| ultrasonic | sound above the range of human hearing (>20,000 Hz) |
| infrasonic | sound below the range of human hearing (<20 Hz) |
| sonar | a technique of using sound waves to measure distance |
| eardrum | the stretched membrane in the ear that transfers the vibrations of sound waves to the middle ear |
| echo | reflected sound waves that return to the source of the sound |
| doppler effect | change of sound that occurs when either the source or a sound or its observer is moving |
| density | the mass per unit volume of a substance |
| elasticity | how quickly a medium returns to its original position after being disturbed |
| geology | the study of the Earth's crust , rocks and fossils |
| meteorology | the study of weather, atmosphere and climate |
| botany | the study of plants |
| zoololgy | the study of animals |
| entomology | the study of insects |
| ornithology | the study of birds |
| oceanography | the study of the ocean environment |
| ichthyology | the study of fish |
| paleontology | the study of prehistoric plants and animals |
| oncology | the study of tumors |
| microbiology | the study of microscopic organisms |
| tsunami | a giant sea wave caused by a large earthquake or other disturbance of the ocean floor |
| magma | molten rock beneath the Earth's surface |
| lava | molten rock on the surface of the Earth |
