Which instrument is used to measure atmospheric pressure?

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

Answer: (A)

Atmospheric pressure is the force exerted by the air in the atmosphere, and you measure it with a device that responds directly to that pressure. A barometer is built to read air pressure, using either a mercury column or a sealed flexible diaphragm to detect changes in the air pushing on it. As atmospheric pressure changes, the barometer’s reading changes, which is useful for weather forecasting and understanding weather trends. The other tools measure different properties: a thermometer gauges temperature, a hygrometer senses humidity, and an anemometer measures wind speed. So the barometer is the instrument specifically designed to measure atmospheric pressure.