Which one of the following devices is used to measure atmospheric pressure ?

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Q: 33 (NDA-I/2018)

Which one of the following devices is used to measure atmospheric pressure ?

question_subject: 

Science

question_exam: 

NDA-I

stats: 

0,25,6,3,25,2,1

keywords: 

{'barometer': [0, 0, 0, 2], 'ammeter': [0, 0, 0, 1], 'atmospheric pressure': [2, 0, 5, 1], 'lactometer': [0, 0, 0, 1], 'potentiometer': [0, 0, 1, 1], 'devices': [0, 1, 0, 7]}

The correct answer is option 2: Barometer.

To understand why a barometer is used to measure atmospheric pressure, let`s explore the other options:

Option 1: Ammeter. An ammeter is a device used to measure electric current. It is not used to measure atmospheric pressure.

Option 3: Potentiometer. A potentiometer is a device used to measure potential difference or voltage. It is not used to measure atmospheric pressure.

Option 4: Lactometer. A lactometer is a device used to measure the density of milk. It is not used to measure atmospheric pressure.

Now let`s explain why a barometer is the correct answer. A barometer is a scientific instrument that is specifically designed to measure atmospheric pressure. It consists of a long glass tube filled with mercury, with one end closed off. The open end is placed in an inverted container filled with mercury. As the air pressure changes, it exerts a force on the mercury in the container, causing it to rise or fall in the tube. The height of the mercury in the tube is a measure of the atmospheric pressure.

Therefore, a barometer is used to measure atmospheric pressure.