The “Julia Child” of kids’ hands-on science
Loudness is measured in decibels, dB for short. Complete silence is 0 dB, a whisper is 10 dB, normal conversation is 60 dB or about 10,000 times louder than a whisper. A lawnmower is 90 dB, about 1,000 times louder than a conversation and a jet engine is 120 dB about 1,000,000 times louder than a conversation. Anything over 85 dB does damage to our ears. That’s because sound traveling through air is a force beating against delicate eardrums. Yes, rock concerts damage ears.
Performing musicians often have tiny earpieces in their ears. This way the sound engineers can send them the sounds of their own voices or instruments, so that they can hear themselves over the other musicians. Those pieces are not for protection. So the dB level of rock concerts can affect those musicians’ hearing. There is even a name for it: Noise Induced Hearing Loss or NIHL. Rock musicians are the top profession to suffer NIHL later in life.
But there is a new threat to hearing loss—the earbuds people use to listen to music from their electronic devices. They are fine if you keep the volume down. But if you’re hooked on loudness that invades all your senses so that you can’t “hear yourself think” and you listen for several hours a day, you’ll pay the price down the road.
Your ability to hear high tones is the first to go. Here’s a quick and easy hearing test you can use on yourself and your family: Turn on the TV and hit the “mute” button or turn the volume all the way down. Lean over the back of the set and listen for a very soft, high-pitched whine. If you can hear it, you are listening to the highest sound the human ear can hear. (Dogs, of course, can hear much higher sounds, hence the dog whistle, which people can’t hear but dogs can.) Walk away from the set to find the distance when you can no longer hear it. Do the same test with your parents. Bet your hearing is better than theirs.
Try listening to some old-fashioned, melodic, soft popular music that came before rock and roll. You just might like it.
" "Fun!" comes through loud and clear in this energetic exploration of hearing and auditory perception. Cobb gets the anatomy lesson out of the way, then moves on to a series of simple activities to help kids experiment with their own sense of hearing. Students investigate sound conduction, perception of pitch, echolocation, and range of hearing by doing such things as sticking fingers in their ears while they talk."
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Vicki Cobb is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.
Huge numbers of periodical cicadas (they're buzzy insects) are coming to fourteen states this spring. Will yours be one of them? Lawrence Pringle will break the news to you tomorrow.