Which instrument is used to measure air pressure?

Which instrument is used to measure air pressure?

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

Answer: (C)

Air pressure is the weight of the atmo­sphere pushing on surfaces. The instrument that measures this pressure is a barometer. In a classic mercury barometer, atmospheric pressure pushes on the mercury, changing the height of the column, and that height indicates the pressure. There are also aneroid barometers that use a sealed metal chamber that flexes with pressure and moves a dial. The other devices measure different things: a thermometer gauges temperature, a sphygmomanometer measures blood pressure, and an anemometer measures wind speed. So, a barometer is used to measure air pressure.

Air pressure is the weight of the atmo­sphere pushing on surfaces. The instrument that measures this pressure is a barometer. In a classic mercury barometer, atmospheric pressure pushes on the mercury, changing the height of the column, and that height indicates the pressure. There are also aneroid barometers that use a sealed metal chamber that flexes with pressure and moves a dial. The other devices measure different things: a thermometer gauges temperature, a sphygmomanometer measures blood pressure, and an anemometer measures wind speed. So, a barometer is used to measure air pressure.