Check the accuracy of my wording for these first two equations, then, if you could, try to explain the last equation for me. Ʃ F = dp/dt "The total net force acting on a particle is equal to the rate of change of momentum over time." ∫ Ʃ F dt = ∫ dp/dt dt "The sum of the total net force acting on a particle over a time interval is equal to the sum of the rate of change of momentum over a time interval." My physics book breaks up differentials like this very regularly so as to make it clear for integration. But my question is, is this step a meaningful equation, or is this simply mathematical notation? Ʃ F dt = dp Thanks!