What is "speed of sound"

n. (context physics English) The speed at which sound is propagated through some medium under specified conditions.

The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium. In dry air at 20 °C (68 °F), the speed of sound is , or a kilometre in or a mile in .

The speed of sound in an ideal gas depends only on its temperature and composition. The speed has a weak dependence on frequency and pressure in ordinary air, deviating slightly from ideal behavior.

In common everyday speech, speed of sound refers to the speed of sound waves in air. However, the speed of sound varies from substance to substance: sound travels most slowly in gases; it travels faster in liquids; and faster still in solids. For example (as noted above), sound travels at in air; it travels at in water (4.3 times as fast as in air); and at in iron. In an exceptionally stiff material such as diamond, sound travels at ; which is around the maximum speed that sound will travel under normal conditions.

Sound waves in solids are composed of compression waves (just as in gases and liquids), but there is also a different type of sound wave called a shear wave, which occurs only in solids. These different types of waves in solids usually travel at different speeds, as exhibited in seismology. The speed of a compression sound wave in solids is determined by the medium's compressibility, shear modulus and density. The speed of shear waves is determined only by the solid material's shear modulus and density.

In fluid dynamics, the speed of sound in a fluid medium (gas or liquid) is used as a relative measure for the speed of an object moving through the medium. The ratio of the speed of an object to the speed of sound in the fluid is called the object's Mach number. Objects moving at speeds greater than are said to be traveling at supersonic speeds.

"Speed of Sound" is a song by British alternative rock band Coldplay. It was written by all members of the band for their third studio album, X&Y (2005). Built around a piano riff, the song builds into a huge, synthesiser-heavy chorus. It was released by Parlophone Records as the lead single from the album. "Speed of Sound" was released in the US on 18 April 2005, and then made its radio premiere on BBC Radio 1 with Lamacq on the day of the release on 19 April. The single was pressed with two B-sides: "Things I Don't Understand" and "Proof". The song premiered in the UK on 23 May.

Coldplay vocalist Chris Martin admitted that the song was developed after the band had listened to English art rock singer Kate Bush. The song's drum beat is similar to Bush's 1985 song " Running Up That Hill". Upon the song's release, it charted in the UK Singles Chart in the number two position. In the United States, it debuted at number eight on the Billboard Hot 100, their first top ten hit in the country, and their most successful song until " Viva la Vida" reached number one in 2008.

"Speed of Sound" was recognised Song of the Year by the American Society of Composers, Authors and Publishers (ASCAP) and it was nominated twice at the 48th Grammy Awards. The song won a Brit Award in the category for Best British Single in 2006. The track's music video was nominated for four MTV Video Music Awards. "Speed of Sound" was also the billionth song downloaded from the iTunes Store.

The speed of sound is a physical characteristic.

Speed of sound may also refer to:

• "Speed of Sound" (song), by Coldplay
• The Speed of Sound (EP) by In Stereo (band), 2016
• "Speed of Sound", a song from the Pearl Jam album Backspacer
• Speed of Sound (album), by Canadian heavy metal band Anvil
• Speed of Sound (Nick Phoenix album), 2013 album by Nick Phoenix
• The Speed of Sound (album), by American rock guitarist Ronnie Montrose
• Speed of Sound (roller coaster), a rollercoaster at Walibi Holland themepark in The Netherlands

Speed of Sound is the ninth studio album by Canadian heavy metal band Anvil.

Speed of Sound is a hybrid electronic/orchestral album released by Two Steps from Hell composer Nick Phoenix in 2013 on iTunes, Amazon and CDBaby. Although released publicly under Phoenix's name, the album is considered part of the Two Steps from Hell catalog, and is featured on ExtremeMusic.com with several alternate versions of the original 20 tracks.

Speed of Sound is a Boomerang roller coaster in Walibi Holland. It was manufactured by Vekoma and opened in 2000 as La Via Volta. It was open until 2007 when the park announced it would be shut down. That year, the train was sold to Pleasurewood Hills in England and now operates on Wipeout and the track remained in place at Walibi World. On 30 January, Walibi Holland announced that the La Via Volta will reopen in 2011, with a new style train from Vekoma under the name of Speed of Sound. P&P Projects was responsible for the design and build of this new attraction. Walibi Holland announced that it held a competition to win tickets for the opening of the roller coaster on April 6, 2011 Competition to win tickets for the first ride, ''Walibi.com, 2011