Question

What is the average value of barometric atmospheric pressure at sea level?
(a) 76 cm of Hg
(b) 76 cm of water
(c) 76 cm of air
(d) 24 cm of Hg

Answer 1

As we know that atmospheric pressure is measured in Hg, which is the symbol of mercury so, we will use the information regarding the pressure at the sea-level. Since, the question asks about the average atmospheric pressure at sea-level so we will answer only the average value.

Complete step by step answer:
Barometric atmospheric pressure: The barometric pressure present in the atmosphere is defined as the pressure that is created by air present in the atmosphere. Here, we are focusing on the air which is above our level of height. We can call barometric pressure as atmospheric pressure. This can be measured by the amount of force in a small unit of area. This pressure is usually measured with a mercury barometer. By the use of the mercury barometer we get to know the height of mercury that helps in balancing weight of the atmosphere. The units by which we can define atmospheric pressure are millimeters of mercury or we can also use inches of mercury.
The standard atmospheric pressure at the sea-level is 29.92 inches which is also 760mm in millimeters and 76 cm in centimeters of mercury.
Atmospheric pressure happens due to the gravitational force which attracts the atmospheric gases present in the air above our height. After some time several modifications have been made with velocity of wind and the changes in the densities due to temperature change.

So, the correct answer is “Option A”.

Note: In our day today life we will come across the news related to it through technical gadgets like radios, televisions or newspapers. The Internet is also a simple source to gain information about the atmospheric pressure at sea-level. The 76 cm of Hg is just the average atmospheric pressure that is recorded by the information of it during times. But there was a time in which the highest atmospheric pressure was recorded on the Earth whose value was 32.03 Hg.