New! Sign up for our free email newsletter.
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
 


Matter & Energy News

November 4, 2026

Scientists have discovered that a simple mechanical squeeze can dramatically alter the magnetic properties and electrical behavior of exotic materials called altermagnets. The surprising breakthrough could open the door to faster, more ...
MIT scientists have challenged two decades of conventional thinking by discovering that flexible molecular connections, rather than rigid ones, can unlock entirely new ways to arrange nanoparticles. ...
For nearly 90 years, scientists believed magnetism fell into just two categories, but researchers have now confirmed a remarkable third type called altermagnetism. Using specialized X-rays, they ...
Mysterious particles called neutrinos constantly stream through our bodies, and scientists are now detecting incredibly powerful versions arriving from distant cosmic sources using a massive ...
Scientists have built a groundbreaking molecular motor that spins in either direction using electricity, inspired by a machine invented more than 2,000 years ago. Even more remarkably, its rotation can boost electrical conductivity by up to 100 ...
Scientists have developed a new technology that could make electric vehicle batteries smaller, lighter, and longer-lasting, potentially allowing cars to travel farther on a single charge. By borrowing precision manufacturing techniques from computer ...
Scientists at UC San Diego have developed a surprising new way to store digital information using light instead of magnets, potentially paving the way for smaller, faster, and more energy-efficient memory devices. By precisely shaping and shrinking ...
Researchers have developed a groundbreaking 3D invisibility cloak that can hide complex objects from infrared cameras while protecting them from extreme heat and cold. Instead of blocking heat, the ...
Scientists have filmed tiny magnetic vortices called skyrmions melting out of an organized lattice for the first time, revealing new ways to manipulate these unusual structures. The breakthrough could help make brain-like computers a reality, ...
A superconducting material studied for 40 years has turned out to be far more complex than scientists believed. Advanced 3D imaging revealed a hidden patchwork of crystal structures, with unusually ...
Researchers have solved a long-standing challenge in understanding how tiny defects in materials like diamond and silicon carbide behave when exposed to light. Their new computational method revealed a surprisingly important energy-loss mechanism in ...
Researchers have developed a revolutionary microscope that uses an incredibly powerful laser to make previously invisible cellular structures easier to see. The technology dramatically improves image clarity, allowing scientists to examine small ...

Latest Headlines

updated 12:56 pm ET