Sound waves: Frequency of sound waves(pitch):20--25000 Hz The intensity of sound waves: Decibel scale B=101og70 =10-12W/m2 Business office Heavy truck Jet take-off 50 6) Loudness (dB)Sound waves: Frequency of sound waves(pitch): 20--25000 Hz The intensity of sound waves: Decibel scale I0=10-12 W/m2