This wave pattern occurs often in nature, including wind waves, sound waves, and light waves. The human ear can recognize single sine waves as sounding clear because sine waves are representations of a single frequency with no harmonics.
Sound and water waves, for example, can be represented as sinusoids, and simple harmonic motion—such as that of a pendulum or a weight attached to a spring—results in a sinusoidal relationship between position and time.
Sine waves are used in technical analysis and trading to help identify patterns and cross-overs related to oscillators.
Since no phenomenon is completely periodic (nothing keeps repeating from minus infinity to infinity), you could say that sine waves never occur in nature. Still, they are a good approximation in many cases and that is usually enough to consider something physical.
A sine wave is a simple periodic sound. Musical instruments or the voice produce complex periodic sounds. They have a spectrum consisting of a series of harmonics. Each harmonic is a sine wave that has a frequency that is an integer multiple of the fundamental frequency.
All string and wind instruments produce pure sine waves. The thing is, usually they produce more than one of them at a time, at multiples of the root.
Each of our voices have the exact same building blocks of sine waves. If you and I were to sing the same note and then play them back using a sound spectrum analyzer, we'd be able to see and hear the same sine waves present in each of our voices.
A sinusoidal or sine wave is a curve with periodic oscillations. While a normal sine wave has periodic oscillations, life's waves aren't as periodic. But, they're just as predictable. Some days are “up” days and other days are “down” days.
The sound wave from the flute is very smooth and looks like a sine wave from a mathematics textbook. A flute has a strong fundamental frequency of 262 Hz and practically no other harmonics or overtones. A musician might describe a flute as having a very pure tone.
Electrical power can be graphically depicted as a sine wave whereby the electrical signal alternates from +120 volts to -120 volts at a rate of 60 times per second (60 Hz).
Applying the Law of Sines in real life involves the areas of architecture, aerodynamics, physics, and other scientific branches. More real-world examples include heights according to angles of depression and elevation.
The sine wave pattern is one of the manifestations of severe hyperkalemia. The sine wave pattern depicts worsening cardiac conduction delay caused by the elevated level of extracellular potassium. The morphology of this sinusoidal pattern on ECG results from the fusion of wide QRS complexes with T waves.
There are three major types of sine inverters – pure sine wave (or “true” sine wave), modified sine wave (actually a modified square wave) and square wave.
Sine is "opposite over hypotenuse" (the SOH of SOHCAHTOA). When we draw the triangle inside a unit circle the hypotenuse is automatically 1 at any angle. That means the sine of an angle is simply the length of the "opposite" leg of the triangle (opposite / 1).
Quick Physics:
Sound is a wave that caused by vibrations in the air. A pure musical sound, such as a whistle, will produce a sine wave like the one shown above.
This combination of many sines waves that are all integer multiples of the fundamental is what gives a piano its distinctive sound. If just the fundamental sine wave vibrated when you pressed a key, it would sound like a cheap alarm clock.
The sound of the flute is a little like a sine wave (a very pure vibration) when played softly, but successively less like it as it is played louder. To make a repeated or periodic wave that is not a simple sine wave, one can add sine waves from the harmonic series.
Sine Wave Syndrome (SWS), also known as Sine Wave Effect (SWE), or mood phase shift keying, is an enervating condition where one's mood keeps changing. It can emerge from negative thinking, overthinking, living a non-structured life, or not being competent regarding what drives you.
Sine waves are one of the most common forms of electrical or electronic waveform. Sine waves are the waveform that is seen when displaying electrical supply or mains waveforms, most RF or radio frequency waveforms, as well as some audio test signals.
All sounds in nature are fundamentally constructed of sine waves. More complex sounds simply contain more oscillations at different frequencies, stacked one upon another. Higher-frequency, oscillations which are tonally related to the fundamental frequency (the base note or tone) are known as harmonics.
“The standard answer is that a completely pure tone is a sine wave tone,” says Aksnes, “that is, an even Hertz frequency that forms an s-shaped sine wave.”
For a single-frequency sound wave, the rate at which it does this is regular and continuous, taking the shape of a sine wave. Thus, the graph of a sound wave is a simple sine wave only if the sound has only one frequency component in it – that is, just one pitch.
Lower notes on the piano produce a squarish sine wave, whereas the higher notes produce an almost perfect sine wave. This is due to overtones produced by the instrument itself. When the lower notes are struck, the low frequency causes the entire instrument to resonate, causing interference with the string's sound wave.