If the kinetic theory o f gases is applied to a mixture of gases, the expression for the pressure becomes:
p = + An2m2< c 2> + An3m3< c 2> + .. .
damped harmonic motion is a simple harmonic motion in which amplitude dimin ishes with time as a consequence of a small damping force impeding the motion. A typical example is a simple pendulum oscillating in air. The drag on the pendulum bob is proportional to the speed of the bob, so when the bob is stationary, the drag force is zero. Because the speed rises and falls periodically, so does the drag force.