Question

Which instrument is used to measure air pressure?
A. Barometer
B. Radiosonde
C. Thermometer
D. Voltmeter

Answer 1

Hint – Barometer is the instrument used to measure the atmospheric pressure. We have been asked about the instrument to measure air pressure.

Complete answer:
Now, out of the given instruments, only a Barometer is used to measure air pressure.
A barometer uses mercury. The atmospheric pressure presses down on a reservoir of mercury and the mercury is forced up in the tube to a certain distance depending on the amount of pressure exerted by the air.
A simple barometer contains a long tube of glass which is closed at one end and open at the other end, full of mercury.
The air pressure is often recorded as mm Hg.
The other instruments mentioned in the options are not used for measuring atmospheric pressure or air pressure.
The radiosonde measures pressure, temperature and relative humidity.
Thermometer measures the temperature and voltmeter is for measuring voltages.

Hence, the correct option is A. Barometer.

Note – Whenever such types of questions appear, then always see the options and then find out which one is the correct option. Out of the given options, only the barometer is the instrument which uses mercury and measures the air pressure. A barometer is a technical instrument used in meteorology to measure the air pressure.