Question

Answer the following questions related to atmospheric pressure.
(i) What is atmospheric pressure?
(ii) Name the instrument used for measuring atmospheric pressure.
(iii) How do altitude, temperature and humidity influence atmospheric pressure?

Answer 1

Instructions:

• Define atmospheric pressure
• Name the instrument used for measuring atmospheric pressure
• Explain how altitude, temperature and humidity influence atmospheric pressure

Solution:
Air has weight. So, the pressure that is exerted on the surface of the earth as a result of its weight is known as atmospheric pressure.

A barometer is an instrument that measures atmospheric pressure.

Altitude, temperature and humidity influence atmospheric pressure in the following ways:

• Altitude: With the rise in height, air pressure reduces. This is because air becomes rarer or less dense with an increase in height.
• Temperature: high temperature leads to the formation of a low-pressure zone as warm air rises upwards, while low temperature creates a high-pressure region.
• Humidity: moist air or air with high water vapour is lighter than dry air, creating low pressure.