Task: Text Categorization
Input (English): By the equivalence principle, a homogenous gravitational field is equivalent to this quantity. The time derivative of this quantity is jerk. In the kinematic equation for position as a function of time, this quantity is the coefficient of the time-squared term, because it is the (*) second derivative of position. By Newton's Second Law, it is equal to force over mass. For 10 points, name this quantity that is the ""a"" in ""F equals m a. ""
Output (English): Science