Reference Terms
from Wikipedia, the free encyclopedia
Speed of sound
The speed of sound is a term used to describe the speed of sound waves passing through an elastic medium. The speed varies with the medium employed (for example, sound waves move faster through water than through air), as well as with the properties of the medium, especially temperature. The term is commonly used to refer specifically to the speed of sound in air. At sea level, at a temperature of 21 degrees Celsius (70 degrees Fahrenheit) and under normal atmospheric conditions, the speed of sound is 344 m/s (1238 km/h or 770 mph). The speed varies depending on atmospheric conditions; the most important factor is the temperature. Humidity has little effect on the speed of sound, nor does air pressure by itself. Air pressure has no effect at all in an ideal gas approximation. This is because pressure and density both contribute to sound velocity equally, and in an ideal gas the two effects cancel out, leaving only the effect of temperature. Sound usually travels more slowly with greater altitude, due to reduced temperature.
Related Stories
1
2
Matter & Energy News
October 6, 2026
Oct. 5, 2026 Scientists have discovered evidence of altermagnetism in a thin, highly tunable material that could help electronics use electron spin instead of relying only on electrical charge. The unusual magnetic state may enable faster, more energy-efficient ...
Oct. 4, 2026 A new light-activated material can efficiently produce hydrogen from water without requiring an additional expensive metal catalyst. Researchers say its unusual sulfur-based chemistry could point toward cheaper and more practical ways to turn ...
Oct. 3, 2026 Researchers have demonstrated that quantum fluctuations in supposedly empty space can strengthen superconductivity, raising the transition temperature of an ultrathin material by as much as 5.4%. The discovery opens the possibility of using ...
Oct. 2, 2026 Ultrashort electrical pulses allowed scientists to push superconductors closer than ever to the point where their electron pairs actually break apart. The method revealed hidden differences between superconducting materials and could open new ways ...
Oct. 1, 2026 Scientists at the University of Chicago have uncovered a surprising quantum state in the layered magnetic material Fe5GeTe2, where huge numbers of electrons move together unusually slowly while remaining quantum coherent. The behavior contradicts ...
Sep. 30, 2026 Researchers have experimentally observed energy patterns that physicists have predicted for about 40 years. By arranging laser-trapped atoms into a quantum simulator, they recreated two different ...
Sep. 29, 2026 Scientists have developed and experimentally demonstrated a long-sought method for identifying W states, an important form of multi-photon quantum entanglement. The technique could make complex ...
Sep. 28, 2026 CosmoCube will use the far side of the Moon as a shield from Earth’s radio noise to search for a faint signal from the universe before the first stars existed. The suitcase-sized satellite could reveal how the cosmic dark ages ended and how dark ...
Sep. 26, 2026 Scientists recreated a particle-forming process linked to the extreme physics of the early universe using a 13-ion quantum simulator. The breakthrough suggests quantum computers could eventually help researchers investigate how matter formed and ...
Sep. 25, 2026 CERN has started replacing some of the Large Hadron Collider’s most important magnets as part of its High-Luminosity upgrade. The new superconducting magnets will produce fields about 40% stronger, allowing particle beams to be squeezed more ...
Sep. 25, 2026 Researchers have shown that exotic quantum particles called non-Abelian anyons can perform the full range of operations needed for universal quantum computing. Using 54 qubits on Quantinuum’s H2 processor, they combined braiding and fusion to ...
Sep. 24, 2026 Researchers have shown that multiple time crystals inside a semiconductor can synchronize their oscillations, much like pendulum clocks gradually falling into the same rhythm. The coupling is carried by spin-polarized electrons, allowing time ...
Latest Headlines
updated 12:56 pm ET
Oct. 6, 2026 Physicists at CERN’s Large Hadron Collider have captured the clearest evidence yet that quark-gluon plasma, the scorching-hot matter that filled the newborn universe, behaves like a true liquid. By ...
Oct. 6, 2026 Researchers have captured key steps in a chemical reaction that helps nature transfer energy with remarkable efficiency. Ultrafast X-rays revealed how changes involving electrons and protons are ...
Oct. 4, 2026 Tiny magnetic fields created shortly after the Big Bang may help explain the long-running disagreement over how fast the universe is expanding. ...
Sep. 24, 2026 Ancient grains inside one of the oldest known meteorites reveal that a surprisingly strong magnetic field existed during the solar system’s first ...
Sep. 22, 2026 Physicists searching through Large Hadron Collider data found no evidence that the machine has been producing microscopic quantum black holes, but the result sharply narrows where such exotic physics ...
Sep. 22, 2026 Stanford researchers have recorded the first real-time quantum jumps of sound, watching single phonons abruptly vanish from one energy state to another. The breakthrough could open new paths for ...
Sep. 21, 2026 Scientists have found evidence that black holes of vastly different sizes may launch powerful jets according to the same universal rule. Supermassive black holes can produce jets soon after tearing ...
Sep. 21, 2026 Scientists at Oak Ridge National Laboratory have developed a surprisingly simple way to turn polyethylene, the common plastic used in shopping bags and cutting boards, into gasoline and diesel-like ...
Sep. 21, 2026 Physicists have put a decades-old idea about why the strange rules of quantum mechanics disappear in our everyday world to one of its toughest experimental tests yet. Deep beneath Italy’s Gran ...
Sep. 20, 2026 Scientists have developed ultra-bright nanoparticles that can detect tiny amounts of chemicals and distinguish between molecules that look almost identical. The technology could one day provide a ...