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SOUNDS & SILENCE
It is amazing how much noise there is in the world. Air-conditioning, motor
cars, aeroplanes and not to mention people, animals and the wind rustling in
the trees.
Sound is carried through the air as a pressure wave. The bigger the pressure
difference the greater the noise level. The faster the frequency of the wave
the higher the sound sounds. Some sounds can be so high that humans
cannot hear them - although many animals can hear much higher
frequencies.
The thunder which accompanies lightning is caused by the sudden heating
of a column of air by the electricity. The air expands quickly creating a
powerful pressure wave which is the sound you hear. It takes longer to get to
you than the lightning because sound travels much slower than light.
Our ears pick up the sound using our eardrums which vibrate when the
sound arrives. Signals are sent to the brain which interprets them as either
loud or soft, high or low and as speech or music and so on.
The Logibloc SOUND BLOC is very sensitive and hears slightly different
sounds to us. Check it out!
