verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies.Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Feedback
Thank you for your feedback
Our editors will review what you’ve submitted and determine whether to revise the article.
Print
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies.Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Feedback
Thank you for your feedback
Our editors will review what you’ve submitted and determine whether to revise the article.
Also known as: stationary wave
Written and fact-checked by
The Editors of Encyclopaedia Britannica
standing wave, combination of two waves moving in opposite directions, each having the same amplitude and frequency. The phenomenon is the result of interference; that is, when waves are superimposed, their energies are either added together or canceled out. In the case of waves moving in the same direction, interference produces a traveling wave. For oppositely moving waves, interference produces an oscillating wave fixed in space.
A vibrating rope tied at one end will produce a standing wave, as shown in the figure; the wave train (line B), after arriving at the fixed end of the rope, will be reflected back and superimposed on itself as another train of waves (line C) in the same plane. Because of interference between the two waves, the resultant amplitude (R) of the two waves will be the sum of their individual amplitudes. Part I of the figure shows the wave trains B and C coinciding so that standing wave R has twice their amplitude. In part II, 1/8 period later, B and C have each shifted 1/8 wavelength. Part III represents the case 1/8 period still later, when the amplitudes of the component waves B and C are oppositely directed. At all times there are positions (N) along the rope, called nodes, at which there is no movement at all; there the two wave trains are always in opposition. On either side of a node is a vibrating antinode (A). The antinodes alternate in the direction of displacement so that the rope at any instant resembles a graph of the mathematical function called the sine, as represented by line R. Both longitudinal (e.g., sound) waves and transverse (e.g., water) waves can form standing waves.
FAQs
Standing waves most often occur in a medium of limited size, in which case they usually fill the entire medium. The duration of a standing wave is then the same thing as how long the wave persists, but unlike with traveling waves that has nothing to do with how large the wave is.
What are the 3 characteristics of standing waves? ›
What are the characteristics of standing waves? Standing waves do not transfer energy . They have nodes and antinodes. They points that form a standing wave are either in phase or anti phase.
What is the best definition of a standing wave? ›
standing wave, combination of two waves moving in opposite directions, each having the same amplitude and frequency. The phenomenon is the result of interference; that is, when waves are superimposed, their energies are either added together or canceled out.
What makes a standing wave special? ›
The two waves have the same frequency since they originate from the same source, and thus the same wavelength since they travel in the same medium. It it clear from the combined wave below why it is called a "standing wave", since we can no longer assign a direction (right or left) to the motion of the wave.
What is true about standing waves? ›
Standing waves are formed by the superposition of two travelling waves of the same frequency (with the same polarisation and the same amplitude) travelling in opposite directions. This is usually achieved by using a travelling wave and its reflection, which will ensure that the frequency is exactly the same.
What is a real life example of a standing wave? ›
A plucked guitar string is a simple example of a standing wave. A plucked string emits a particular sound frequency depending on the string length and how taut or dense the string is. Each string only makes certain notes because only certain standing waves are able to form on that string.
What are the two main parts of a standing wave? ›
Nodes are points of no motion in standing waves. An antinode is the location of maximum amplitude of a standing wave. Normal modes of a wave on a string are the possible standing wave patterns. The lowest frequency that will produce a standing wave is known as the fundamental frequency.
What is the point of standing waves? ›
Standing waves have many real-life applications, including in musical instruments, telecommunications, and medical imaging. In musical instruments, standing waves are responsible for the formation of harmonics and the unique sound of different instruments.
What is another name for a standing wave? ›
In physics, a standing wave, also known as a stationary wave, is a wave that oscillates in time but whose peak amplitude profile does not move in space.
How many waves are in a standing wave? ›
A standing wave occurs when two waves of the same frequency and amplitude are moving in opposite directions and interfere with each other. It has certain points (called nodes) where the amplitude is always zero, and other points (called antinodes) where the amplitude fluctuates with maximum intensity.
The simplest example of a standing wave is one with a node on each end, such as a string that's fixed in place on the ends and plucked. When there is a node on each end and only one antinode in between them, the wave is said to vibrate at the fundamental frequency.
Does a standing wave go anywhere? ›
Standing waves don't go anywhere, but they do have regions where the disturbance of the wave is quite small, almost zero. These locations are called nodes . There are also regions where the disturbance is quite intense, greater than anywhere else in the medium, called antinodes .
Why don't standing waves cancel out? ›
Standing waves do not cancel each other out because of the alignment between the waves. A standing wave occurs when a wave is reflected back and interferes with itself. The nodes of a standing wave occur where the waves do cancel perfectly, or interact destructively, creating a point that does not move.
What does n mean in standing waves? ›
for standing waves in a string, n is equal to the number of antinodes. lambda = 2L/n. for standing waves in an open tube, n is equal to the number of nodes. lambda = 2L/n.