beat

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beat

1. Physics the low regular frequency produced by combining two sounds or electrical signals that have similar frequencies
2. Prosody the accent, stress, or ictus in a metrical foot
3. Nautical a course that steers a sailing vessel as close as possible to the direction from which the wind is blowing
4. 
a. the act of scouring for game by beating
b. the organized scouring of a particular woodland so as to rouse the game in it
c. the woodland where game is so roused
5. Fencing a sharp tap with one's blade on an opponent's blade to deflect it

Beat

A variation in the intensity of a composite wave which is formed from two distinct waves with different frequencies. Beats were first observed in sound waves, such as those produced by two tuning forks with different frequencies. Beats also can be produced by other waves. They can occur in the motion of two pendulums of different lengths and have been observed among the different-frequency phonons in a crystal lattice.

One important application of beat phenomena is to use one object with an accurately known frequency to determine the unknown frequency of another such object. The beat-frequency or heterodyne oscillator also operates by producing beats from two frequencies.

beat

[bēt]
(physics)
The periodic variation in amplitude of a wave that is the superposition of two simple harmonic waves of different frequencies.

beat

i. A low-frequency vibration produced when two sources of vibration act on the same object at the same time. For example, in a multiengine airplane, if two engines have slightly different RPM, airframe vibrations produced by these engines will produce a very noticeable beat.
ii. When two waves are combined or superimposed, a beat occurs if two frequencies are not the same. Waves beat together to create the appearance of either a change in amplitude, if the frequencies differ by a few hertz (Hz), or new frequencies, called beat frequencies or heterodynes, if the original frequencies are far apart.
References in periodicals archive ?
They can't do it." The 30-year-old entrepreneur maintains his company can beat back the portals in auctions because auctions are his only focus.
Countries with a functioning Net beat back a bid by the U.N.
JAPAN -- With summer temperatures rising, cities like Tokyo and Fukuoka have found a cheap, natural way to beat back the swelter of urban "heat islands." This year, the Urban Development Corporation (UDC) began "greening" Tokyo's rooftops with 2.3 hectares of grass.
Proof that we can pass a gay rights bill only by disavowing any interest in affirmative action came in 1998 when we beat back a Republican attack on Clinton's order banning discrimination in federal employment only after much work to make it clear that affirmative action was not involved.
The most important island is Chiloe, a cultural obfuscation cut off from the mainland when the local inhabitants, the Mapuches, beat back the Spanish conquerors in the late 16th century.
Yet not a month later, AMPAC contributed thousands to help pro-tobacco Senators Kit Bond from Missouri and Sam Brownback from Kansas beat back Democratic challengers.
Tax Bill--Industry successfully beat back an attempt by the Clinton administration to include a broad-based energy consumption tax in the budget deficit package.
By taking better aim with both chemical and radiation treatments, cancer researchers have discovered they can pack more power into their antitumor punches -- enough, they hope, to beat back hard-to-treat liver and pancreas cancers.
On Monday, the Syrian Army troops, after hours of non-stop battle, beat back Jeish al-Islam terrorists from Rahbat al-Isharah region, which was one of the most important defense positions of the terrorists near al-Reihan and Douma.
Firefighters had to beat back the flames that were threatening a complex of flats in the California famous hills.
Tim Easterby's gelding, a disappointing favourite at Southwell two outings ago, showed his appreciation for this quicker surface when a close third over six furlongs last time and will be hard to beat back at the minimum trip.