What instrument is used to measure atmospheric pressure?

What instrument is used to measure atmospheric pressure?

• A. Thermometer
• B. Hydrometer
• C. Barometer
• D. Anemometer

Answer: (C)

The instrument used to measure atmospheric pressure is the barometer. Barometers operate based on the principle that atmospheric pressure can be measured by observing the height of a column of liquid (usually mercury or water) in a glass tube. As atmospheric pressure changes, it exerts force on the liquid, causing it to rise or fall within the tube. This reading can then be used to determine the current pressure in the atmosphere, which is essential for weather forecasting and understanding meteorological phenomena.

The other instruments serve different purposes: thermometers measure temperature, hydrometers assess the density of liquids, and anemometers gauge wind speed. Each has its specific application, but only the barometer is designed specifically for measuring atmospheric pressure.