What is Atmospheric Pressure?
Air possesses weight and hence it exerts pressure like liquids because it possesses weight. The atmospheric pressure at a point is defined as the force acting normally on a unit area around that point, due to the total height of the air column of the atmosphere above it.
The value of it is maximum at sea level and decreases as we go to higher altitudes.
Its symbol is Pa and S.I. unit is newton per square meter (N m-2) or pascal (Pa).
Pa = 1.013 × 105 Nm-2.
Atmospheric Pressure
Earth’s atmosphere is like the blanket of many-kilometer high gases which timelessly wraps our planet. One of the basics of gas law is the statement that the air in the atmosphere presses down on us, creating something called air pressure. Luckily, our bodies can counterbalance this impact so we don’t really feel it. The air pressure is the highest next to the Earth’s surface, but it drops as you get higher and higher. This pressure is what we refer as atmospheric pressure, and it is about 1.01325 Pascal at sea level. Our body itself is quite used to this pressure but in very extreme essence like high altitudes, our nose might bleed because the pressure inside is higher than outside.
The gaseous envelope surrounding the earth from all around is called the atmosphere. It extends approximately up to 400 km. It contains air which is 72% nitrogen and 21% oxygen additionally to a little proportion of dioxide, chemical element, etc.