# Why are the waves sinusoidal? ### Why are the waves sinusoidal?

A wave progressive is sinusoidal if thewave 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 thewave 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 ofwave are of the same order of magnitude, we obtain circular wavesof the same length ofwave : 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 thewave of ” mechanical because the disturbance is a deformation of the material medium itself… And we qualify thewave 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 ofwaveswhile 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.