An enumeration district is a geographic area determined for purposes of taking the census. In one city there may be many enumeration districts, so once you enter a city, county, or state, you can narrow your results by entering street level information, or investigate enumeration district maps, or descriptions.
P wave. 1. a longitudinal earthquake wave that travels through the interior of the earth and is usually the first conspicuous wave to be recorded by a seismograph. Also called primary wave. Compare L wave, S wave. The P wave is admitted to be the wave of auricular contraction. p wave.
There are two types of body waves, P-waves and S-waves. Pressure waves or Primary waves (P-waves), are longitudinal waves that involve compression and rarefaction (expansion) in the direction that the wave is traveling. P-waves are the fastest waves in solids and are therefore the first waves to appear on a seismogram.here are two types of body waves, P-waves and S-waves. Pressure waves or Primary waves (P-waves), are longitudinal waves that involve compression and rarefaction (expansion) in the direction that the wave is traveling. P-waves are the fastest waves in solids and are therefore the first waves to appear on a seismogram.