An FM signal has a center frequency of 154.5 MHz, but is swinging between 154.45 MHz and 154.55 MHz at a rate of 500 times per second. Its input intelligence frequency is:

this could be newton#'s law of cooling. the cooling curve is exponential

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me