GEOLOGY

Detailed explanation-1: -A barometer measures atmospheric pressure in units of measurement called atmospheres or bars. An atmosphere (atm) is a unit of measurement equal to the average air pressure at sea level at a temperature of 15 degrees Celsius (59 degrees Fahrenheit).

Detailed explanation-2: -Simply put, barometric pressure is the measurement of air pressure in the atmosphere, specifically the measurement of the weight exerted by air molecules at a given point on Earth. Barometric pressure changes constantly and is always different depending on where the reading takes place.

Detailed explanation-3: -Instruments used to measure and display pressure mechanically are called pressure gauges, vacuum gauges or compound gauges (vacuum & pressure). The widely used Bourdon gauge is a mechanical device, which both measures and indicates and is probably the best known type of gauge.

Detailed explanation-4: -Barometer is an instrument used to measure the atmospheric pressure, while manometer is used to measure the gauge pressure of fluid inside a container.

Detailed explanation-5: -atmospheric pressure, also called barometric pressure, force per unit area exerted by an atmospheric column (that is, the entire body of air above the specified area).