Perception of the energy of a sound Loudness depends on 2 factors

Amount of energyDistance from the source

The greater the sound, the louder the sound

Greater the distance, less intense soundSound only carries so much energyAs sound carries the energy spreads out

P. 43 Loudness is measured in decibel

How high or low a sound is The pitch depends on the frequency of a

waveP. 45

Change in frequency as the source moves

As the source moves towards, the frequency increases

As a sources moves, the motion adds to the waves