Question

a nonzero net force acts on a particle and does work. which one of the following statements is true? the kinetic energy and the speed of the particle change, but the velocity of the particle does not change. the kinetic energy of the particle changes, but the velocity of the particle does not change. the kinetic energy of the particle changes, but the speed of the particle does not change. the kinetic energy, speed, and velocity of the particle change. the kinetic energy of the particle does not change, but the speed of the particle does change.

Explanation:

Step1: Recall work - energy theorem

The work - energy theorem is $W = KE_f-KE_0$. Since work $W
eq0$, the kinetic energy changes. As $KE=\frac{1}{2}mv^{2}$, and mass $m$ is constant, the speed $v$ must change.

Step2: Understand relationship between speed and velocity

Speed is the magnitude of velocity. If the speed changes, the magnitude of the instantaneous velocity changes, so the velocity changes.

Answer:

The kinetic energy, speed, and velocity of the particle change.