The intensity of sound that does not cause ear damage-
Ans. is 'a' Le., 80 o Intensity is the strength of sound which determines its loudness. It is usually measured in decibels (dB). o Following are intensities when a person is at a distance of one meter from a sound source. Whisper 30 dB Normal conversation 60 dB Shout 90 dB Discomfort of ear 120 dB Pain in ear 130 dB o A daily exposure up to 85 dB is the about the limit people can tolerate without substantial damage to their hearing.
80
100
120
150
Environment and Health