physics 101

*for simplicity's sake, we'll talk just of sound waves in air.
the speed at which sound propagates is influenced directly by both a) the density of the medium through which it travels & b) the factors affecting the medium (such as humidity, altitude & temperature). while sound speed in air is determined by the air itself... it is not dependent upon the sound's amplitude, frequency or wavelength to calculate the speed of sound in dry air at sea level (normal atmospheric pressure).... so we approximate by the following equation:
v = 331.4 + 0.6tc
v = velocity (m/s); tc = temperature in celsius

still with me?

at normal atmospheric pressure and a temperature of 20° celsius, a sound wave will travel at approximately 343 m/s (equal to about 750 miles per hour). by comparison..... the speed of light (in a vacuum) is *299,792,458 meters per second (186,000 miles per second). for anyone who doesn't want to do the math.. that's about 870,000 times faster than the speed of sound in our equation.

now..... my point is simply this:
*this difference between the speed of sound & the speed of light is why sometimes, some people appear brilliant... until you hear them speak.*