Earnings: Amgen, Inc., United States Steel Corporation, Western Digital, More (AMGN, X, WDC, More) January 27, 2015. After the bell on Tuesday, a number of big name, dividend paying companies announced their quarterly earnings. Below, we look at these earnings reports and break down the important points for investors.
As temperature increases, the density of liquids and gases decreases; as temperature decreases, the density increases. Density is the amount of mass per unit of volume.
Therefore, the air pressure is lower. Air temperature changes as you go higher above the earth. Since the surface of the earth heats the air above it, the air is warmer near the ground. Air pressure on the earth's surface also changes. Changes in temperature cause changes in air pressure. As the air near the surface of the earth becomes warmer, the particles becomes warmer, the the particles of the air move farther apart. The air becomes lighter and rises. The lighter air pushes down on the surface of the earth with less pressure.