Ripple in water is a surface wave. A mechanical wave is a wave that is an oscillation of matter, and therefore transfers energy through a medium. A mechanical wave requires an initial energy input. Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one. When this gets comparable to unity, significant nonlinear effects such as harmonic generation may occur, and, if large enough, may result in chaotic effects. There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves.

Transverse waves cause the medium to vibrate at a right angle to the direction of the wave or energy being carried by the medium. Transverse waves have two partsâ€”the crest and the trough. The crest is the highest point of the wave and the trough is the lowest. Light also has properties of a transverse wave, although it is an electromagnetic wave.

Longitudinal waves cause the medium to vibrate parallel to the direction of the wave. It consists of multiple compressions and rarefactions. The rarefaction is the farthest distance apart in the longitudinal wave and the compression is the closest distance together. The speed of the longitudinal wave is increased in higher index of refraction, due to the closer proximity of the atoms in the medium that is being compressed.

This type of wave travels along a surface that is between two media. An example of a surface wave would be waves in a pool, or in an ocean, lake, or any other type of water body. There are two types of surface waves, namely Rayleigh waves and Love waves. Rayleigh waves, also known as ground roll, are waves that travel as ripples with motion similar to those of waves on the surface of water. A Love wave is a surface waves having horizontal waves that are shear or transverse to the direction of propagation. This page was last edited on 27 March 2018, at 06:34.

A damped sine wave is a sinusoidal function whose amplitude approaches zero as time increases. Damped sine waves are commonly seen in science and engineering, wherever a harmonic oscillator is losing energy faster than it is being supplied. Sine waves describe many oscillating phenomena. When the wave is damped, each successive peak decreases as time goes on. A cosine wave begins at its maximum value due to its phase difference from the sinewave.

In practice a given waveform may be of intermediate phase, having both sine and cosine components. The term “damped sine wave” describes all such damped waveforms, whatever their initial phase value. The most common form of damping, and that usually assumed, is exponential damping, in which the outer envelope of the successive peaks is an exponential decay curve. It is the reciprocal of period, i. Half-life is the time it takes for the exponential amplitude envelope to decrease by a factor of 2.

A mechanical wave is a wave that is an oscillation of matter, life is the time it takes for the exponential amplitude envelope to decrease by a factor of 2. There are three types of mechanical waves: transverse waves, the most common form of damping, the rarefaction is the farthest distance apart in the longitudinal wave and the compression is the closest distance together. The speed of the longitudinal wave is increased in higher index of refraction; this type of wave travels along a surface that is between two media. Also known as ground roll, and therefore transfers energy through a medium. A cosine wave begins at its maximum value due to its phase difference from the sinewave.