Question

What is the effect of height on barometric pressure? Explain your answer by drawing a graph.

Answer 1

Step 1 : Effect of height on barometric pressure

1. Barometric pressure is inversely proportional to the height or altitude.
2. Higher we go, the lesser will be the barometric pressure.
3. As we go up, the length of the air column exerting pressure decreases, and as a result of which atmospheric pressure decreases.
4. If we go inside a mine, the length of the air column increases, and as a result of which atmospheric pressure increases.
5. Moreover, while going upward, the density of air decreases which causes a reduction in the atmospheric pressure because atmospheric pressure is directly proportional to the density of air.

Step 2: Graphical explanation

The graph below shows the variation of barometric pressure or atmospheric pressure with height.

From the graph, the following points can be observed:

1. On the sea-level surface, atmospheric pressure is maximum and is equal to 76 cm of mercury.
2. As the height above the sea level increases, atmospheric pressure keeps on decreasing.
3. It is clear from the graph that with increase in height, the atmospheric pressure decreases.