Mechanical Waves are waves which propagate through a material medium (solid, liquid, or gas) at a wave speed which depends on the elastic and inertial properties of that medium. There are two basic types of wave motion for mechanical waves: longitudinal waves and transverse waves. The animations below demonstrate both types of wave and illustrate the difference between the motion of the wave and the motion of the particles in the medium through which the wave is travelling.
If the temperature of the air is said to be at absolute zero, one might conclude that a. the molecules contain a minimum amount of energy. b. the motion of the molecules is at a maximum. c. the molecules are occupying a large volume. the molecules contain a minimum amount of energy.
There are also two entirely different concepts, absolute humidity and relative humidity. The measurements given in the weather forecasts are relative humidity. The Relative Humidity expresses how much moisture is in the air, as a percentage of the total moisture the air could contain at the current temperature. In other words, if the air has all the water vapor that it can contain at a given temperature, the relative humidity is 100%.