1. Hearing and Mechanoreceptors

2. Waves of compression move from a sound source.

3. Frequency = how many waves pass a point/ unit time = cycles per second = Hertz
Wave height = amplitude
Wave length

4. Range of human hearing 20 Hz to 20,000 Hz
Children – up to 25,000 Hz
Dogs – up to 40 kHz
Bats – up to 100 kHz
Intensity if proportional to amplitude squared. A decibel scale is used where 0 is the threshold of human hearing (10 watts/m2)
Loudness is related to intensity but it also influenced by frequency. We are more sensitive to sounds in the 2-4kHz range