An ambulance siren sounds different as it approaches you than when it moves away from you. What scientific term would you use to explain how this happens?
A. ultrasound
B. diffraction
C. rarefaction
D. the Doppler effect
The part of the ear that sends coded nerve signals to the brain is
A. the outer ear.
B. the inner ear.
C. the middle ear.
D. the eardrum ***
To what is amplitude related?
A. the amount of energy carried by the wave
B. the maximum displacement from the rest position
C. neither of the above
D. both the first and the second choices above.