Liquid sulfur changes shape and goes critical under pressure

Scientists from the ESRF, together with teams from CEA and CNRS/Sorbonne Université, have found the proof for a liquid-to-liquid transition in sulfur and of a new kind of critical point ending this transition. Their work ...

New study detects ringing of the global atmosphere

A ringing bell vibrates simultaneously at a low-pitched fundamental tone and at many higher-pitched overtones, producing a pleasant musical sound. A recent study, just published in the Journal of the Atmospheric Sciences ...

Earth's lower mantle can be oxidized in the presence of water

If we took a journey from Earth's surface to the center, the midway point is roughly at 1900 km depth in the lower mantle. The lower mantle ranges from 660 to 2900 km depth and occupies 55% of our planet by volume. The chemical ...

High-quality boron nitride grown at atmospheric pressure

Graphene Flagship researchers at RWTH Aachen University, Germany and ONERA-CNRS, France, in collaboration with researchers at the Peter Grunberg Institute, Germany, the University of Versailles, France, and Kansas State University, ...

The candy-cola soda geyser experiment, at different altitudes

Dropping Mentos candies into a bottle of soda causes a foamy jet to erupt. Although science fair exhibitors can tell you that this geyser results from rapid degassing of the beverage induced by the candies, the precise means ...

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Atmospheric pressure

Atmospheric pressure is sometimes defined as the force per unit area exerted against a surface by the weight of air above that surface at any given point in the Earth's atmosphere. In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Low pressure areas have less atmospheric mass above their location, whereas high pressure areas have more atmospheric mass above their location. Similarly, as elevation increases there is less overlying atmospheric mass, so that pressure decreases with increasing elevation. A column of air one square inch in cross-section, measured from sea level to the top of the atmosphere, would weigh approximately 65.5 newtons (14.7 lbf). The weight of a 1 m2 (11 sq ft) column of air would be about 101 kN (10.3 tf).

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