Show I Piano Is Tuned Out otI of ot I Tune Speed of Sound The piano is always purposely tuned out of tune observes a writer in the Portland Oregonian The true diatonic scale has the vibration ratios ratios ratios ra ra- ra- ra 1 9 8 5 4 4 3 32 3 53 5 8 15 2 2 This scale is used for instruments like the violin where accurate tuning tun ing is possible For the piano the constant ratio for Cor semitones is the twelfth root of 2 which is This Thus flattens D Dand Dand Dand and G and sharpens E F A and B. B The piano uses only one black key for Cor C sharp and D flat although C sharp has the ratio of 25 24 to C and md D flat has the ratio of 25 24 to toD toD toD D which according to the diatonic scale would give two distinct tones The actual tuning of the piano to international pitch is based upon vibrations assigned to the A above middle C and this flattens all the theother theother theother other notes of the scale slightly The velocity or speed of sound depends upon the medium through which the sound is transmitted as aswell aswell aswell well as upon its density and the temperature At ordinary temperatures sound travels through the air at the rate of about 1090 feet per second or about 12 miles per minute Thus if the thunder is heard five seconds after the flash of lightning is seen the flash occurred at the distance of about one mile Through hydrogen sound will travel at the speed of feet per second or nearly four times as fast as in ordinary air In water it travels travels travels trav trav- els feet per second or about 4 times as fast as in air Compared Compared Compared Com Com- pared with its speed through air sound travels 10 times as fast in pine 11 II times as fast in copper 15 times as fast in steel and aluminum and 17 times as fast in glass |