Skip to main content

if you change the amplitude, of a sound wave, you change its ....

Q: If you change the amplitude of a sound wave, what do you change?


A: If you change the amplitude of a sound wave, you change its power and intensity. You also change its perceived loudness. In more general terms, you are changing the energy content of a sound wave when you change its amplitude. The amplitude of a sound is a measure of the change in pressure (force over a given area) that it exerts on the air through which it passes. 


The power of a sound is its amplitude over a given period of time. Power, like electrical power, is expressed in Watts, which is equal to 1 Newton of force per second. An increase in amplitude therefore causes a corresponding increase in power.


Sound is a 3D phenomenon. It radiates in a sphere from the source that creates it (like a speaker, human voice, airplane, or musical instrument). The power of a sound is the total force exerted by this sphere. Intensity is the power (as defined above) of the sound divided by a square unit area (usually per square meter). Intensity is usually measured in decibels (dB). This is a logarithmic measure because both power and intensity are proportional to the square of the sound's amplitude. That is, doubling the amplitude of a sound will actually quadruple the sound's power and intensity. Therefore, decibels, a logarithmic scale, are used to make the units on the measurement of intensity smaller and more tractable.


In psychological terms (that is, the way that we actually hear sound), changing the amplitude of a sound wave will also change its perceived loudness. Loudness is a function of a sound's intensity and is also measured in decibels (dB). Depending on the loudness of the sound as a function of this change in amplitude, it can vary from being impossible to hear to causing pain and, eventually, hearing loss.

Comments

Popular posts from this blog

etymology - Origin of the greeting "Sweet dreams".

Does anybody know the etymology of the phrase "sweet dreams"? I tried googling but did not find anything satisfying. Is this a relatively new phrase of the modern world or has this been in use for some time? I think it's the latter one. Answer The OED has the interjection as "a farewell to someone going to bed" from the 20th century: 1908 Sears Roebuck Catal. 198/1 Tenor Solos..Good Bye, Sweet Dreams, Good Bye. But it goes back until at least the 19th and possibly 18th centuries. John Wolcot, writing under the pseudonym of Peter Pindar, used it in his poem "Orson and Ellen; A Legendary Tale" published in 1801: Also from 1801 in The infernal Quixote (Page 287) by Charles Lucas: In the March 1776 of The Universal Magazine was published "The Serenade. A Pastoral Tale. From the German of Gesner" , where the shepherd Daphnis watches over his beloved as she sleeps and sings: The same tale appears in 1776's as Idyl XI, " Daphnis ...

Is there a word/phrase for "unperformant"?

As a software engineer, I need to sometimes describe a piece of code as something that lacks performance or was not written with performance in mind. Example: This kind of coding style leads to unmaintainable and unperformant code. Based on my Google searches, this isn't a real word. What is the correct way to describe this? EDIT My usage of "performance" here is in regard to speed and efficiency. For example, the better the performance of code the faster the application runs. My question and example target the negative definition, which is in reference to preventing inefficient coding practices. Answer This kind of coding style leads to unmaintainable and unperformant code. In my opinion, reads more easily as: This coding style leads to unmaintainable and poorly performing code. The key to well-written documentation and reports lies in ease of understanding. Adding poorly understood words such as performant decreases that ease. In addressing the use of such a poorly ...

What are the similarities between the relationships of the characters in The Outsiders and Romeo and Juliet?

At first glance, it might appear as if the characters in  The Outsiders  by S. E. Hinton and  Romeo and Juliet  by William Shakespeare do not have much in common; however, when one isolates the core of the conflicts, it becomes clear that the relationships in both stories are rooted in rivalry and secrecy.  In both  The Outsiders  and  Romeo and Juliet , an overarching theme is rivalry. While   socioeconomic status separates the greasers from the Socs in The Outsiders , last names separates the Montagues from the Capulets, who appear to be relatively equal in terms of socioeconomic status. Due to these rivalries, there are instances of deadly interactions in both stories. In  The Outsiders , Johnny kills Bob (whether his actions were justified or not is debatable). In  Romeo and Juliet , Romeo kills Tybalt and Paris, and Tybalt kills Mercutio. These deaths have profound effects on the main characters. In Ponyboy's case, the Johnny's death and other events in the novel inspire h...