| A | B |
|---|
| pinna | outside ear made of cartilage |
| ear_canal | ***8tube that carries sound waves to the eardrum |
| eardrum | taut membrane that separates the outer ear from the middle eat |
| ossicles | tiniest bones in the body |
| hammer | connected to the eardrum and strikes the anvil |
| anvil | vibrates the stirrup |
| stirrup | vibrates the cochlea |
| cochlea | transforms vibrations into electrical impulses that are sent to the brain |
| semicircular_canals | ***organ that determines the body's orientation in 3 dimensional space |
| hertz | one vibration per second |
| decibel | unit used to measure sound intensity |
| Eustachian | tube below the ossicles that connects to the nasal cavity |
| ultrasound | sound whose frequency is above 20,000 hertz |
| infrasound | sound whose frequency is below 20 hertz |
| Doppler_effect | ***apparent shift of sound frequency caused by compression or rarefaction of sound waves by moving object |
| frequency | number of vibrations per second |
| medium | substance that carries sound energy |
| Mach1 | speed of sound (768 m.p.h.) |
| Chuck_Yeager | ***man who broke the speed barrier |
