# Why are the waves sinusoidal?

**Sommaire de notre article**

- Why are the waves sinusoidal?
- How do you know if a wave is periodic?
- Why is the wave called progressive?
- Why is the wave circular?
- How to determine elongation?
- How to define a traveling wave?
- Why is the wave called mechanical?
- Why does the wave propagate?
- What is the period of a sine wave?
- How to calculate the expression of a sine wave?
- What is sine wave signal?
- What is sine wave?

### Why are the waves sinusoidal?

A **wave** progressive **is sinusoidal** if the**wave** evolves according to time and distance like a sinusoid. In other words, the functions yM(x) and yM

### How do you know if a wave is periodic?

A **wave** progressive **is** said **periodic** when the disturbance reproduces identical to itself at equal time intervals, called time period noted T. For simplicity, we can speak of period for T. The pattern of a **wave is** the disturbance that repeats itself every period.

### Why is the wave called progressive?

And we qualify the**wave** of ” **progressive** because the propagation of the disturbance takes place step by step more or less rapidly.

### Why is the wave circular?

When the size of the opening and the length of**wave** are of the same order of magnitude, we obtain **circular waves**of the same length of**wave** : I’**wave is** diffracted. Plus the size of the opening **is** smaller, the greater the diffraction phenomenon **is** important.

### How to determine elongation?

L’**elongation** of P is given by Y(x) = A. sin(ω. t − φ). Examination of the string with a stroboscope shows that the shape of the string is a sinusoid and therefore that φ(x) = kx

### How to define a traveling wave?

The phenomenon of propagation of a disturbance in a medium is called **traveling wave**. A **traveling wave** propagating in one direction is called **traveling wave** to one dimension. The propagation of a disturbance along a wavescope is a **traveling wave** to one dimension.

### Why is the wave called mechanical?

→ We qualify the**wave** of ” **mechanical** because the disturbance **is** a deformation of the material medium itself… And we qualify the**wave** of “progressive” because the propagation of the disturbance takes place step by step more or less rapidly.

### Why does the wave propagate?

The sound **spreads** thanks to the compression that **to** moves among air molecules. To explain it, we often compare this physical phenomenon to a stone that we throw into the water: we observe that small waves **to** then move to the surface in the form of**waves**while the water remains in its place.

### What is the period of a sine wave?

A progressive sinusoidal wave being a periodic progressive wave, it therefore also has a double periodicity: temporal and spatial. Thus, the notions of period and wavelength are valid for progressive sinusoidal waves.

### How to calculate the expression of a sine wave?

Expression of a progressive sinusoidal wave (not required) A is the amplitude of the wave (unit depending on the wave studied), t is the time (in s), T is the period (in s), x ( in m) is the position along the wave propagation axis, λ is the wavelength (in m).

### What is sine wave signal?

A sinusoidal signal is a signal (wave) whose amplitude, observed at a specific location, is a sinusoidal function of time. The sine function is a function which makes it possible to calculate the sine of an angle (In geometry, the general notion of angle comes in several related concepts.) from the value of this angle.

### What is sine wave?

Define a particular periodic mechanical progressive wave: the sine wave and its characteristics (period, frequency and wavelength). 1. Periodic traveling waves We call traveling wave the phenomenon of propagation of a disturbance, step by step, without transport of matter but with transport of energy.