Topic: atmospheric pressure and manometer

Atmospheric Pressure Air has a weight and it exert pressure on any surface. The earth is surrounded by air with height of about 80km. This Air exert a pressure on the surface or sea level. This pressure is called Atmospheric pressure. It is the pressure exerted by a column of air of height about 80km. The value of atmospheric pressure is about  . This pressure does not really affect human and other animal because the blood pressure is a little higher than the atmospheric pressure. Evidence...