One often draws a free body diagram before applying this law, which requires vector sums of forces.
Applying Ehrenfest's theorem to the momentum operator recovers this equation in quantum mechanics. It can be used to derive a law setting the change in velocity proportional to the logarithm of initial mass over final mass. That equation, the Tsiolkovsky rocket equation, requires a generalized version of this equation since mass is not constant. Integrating this law with respect to time gives the impulse, because the time derivative of momentum appears on one side of it. One often draws a free body diagram before applying this law, which requires vector sums of forces. For 10 points, name this law of mechanics which states that net force equals mass times acceleration.
Applying Ehrenfest's theorem to the momentum operator recovers this equation in quantum mechanics.
Newton's second law of motion [prompt on F = ma]