14.1 : 单个粒子的线性冲量和动量原理

Linear momentum is a vector that shares the same direction as the velocity, while linear impulse measures the effect of a force during the time it acts on the particle.

Consider the equation of motion for a particle of mass m, where acceleration and velocity are measured from an inertial frame of reference.

By integrating the equation with respect to time and rearranging the terms, an equation is obtained which represents the principle of linear impulse and momentum.

It states that the initial momentum of the particle, added to the sum of all the impulses applied to the particle during a specific time period, equals the final momentum of the particle.

These terms can be illustrated using impulse and momentum diagrams.

The momentum diagrams depict the direction and magnitude of the initial and final momentum of the particle, while the impulse diagram represents all the impulses acting on the particle at intermediate points along its path.

The principle can be expressed as three scalar equations by resolving each vector into its components.