Final answer:
The density of air decreases as altitude decreases.
Step-by-step explanation:
The density of air decreases as altitude decreases. This is because as altitude increases, the atmospheric pressure decreases.
The relationship between density and pressure can be described using the ideal gas law, which states that the density of a gas is inversely proportional to its pressure, assuming a constant temperature. As altitude increases, the pressure decreases, leading to a decrease in the density of air.
For example, at sea level where the atmospheric pressure is higher, the air is denser compared to higher altitudes such as mountain peaks where the atmospheric pressure is lower.
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