Math geeks only!
I think I’ve come up with a practical application of the 3rd derivative. My pre-calc teacher agrees with me.
Our application revolves around a car. When the gas pedal is pressed and held at a constant rate, the engine accelerates the car. The 2nd derivative is the rate of acceleration. The 3rd derivative in this instance is the rate at which the gas pedal is depressed, thus accelerating the acceleration.
Ph33r my math skillz.