LS7.0 Sound - Lunchbox Science Note Cards

The Back of the Card says:

LS 7.0 Sound

When something causes vibration of molecules in the air (or water or gas), such as a violin string or blowing air into a flute, beating on a drum, vocal chords, a jet... molecules are set in a back and forth wave motion that propagates energy. when that reaches your ear, the ear drum sets the middle ear bones (anvil, hammer and stirrup) into motion, transmitting the vibrations thru the cochlea to small hairlike nerve cells. The cells send the vibrations as electrical impulses thru the auditory nerve to the brain.

The vibration wave goes back and forth and is measured by frequency or how many vibrations per second called Hertz. Each Hertz is associated with a pitch. Middle C on the piano is 261.6 Hertz.

Humans can hear from 20 to 20,000 Hertz.

Dogs - 50 to 45,000 Hz

Cats - up to 85,000 Hz; bats - 120,000 Hz.; Bats 200,000 Hz. Elephants can hear as low as low as 5,000 HZ, but only as high as 10,000 Hz.

Each card comes as individual or set of 6 of same or variety pack of Eight 4 by 6 Note Cards with envelopes.