# Types of waves

### Types of waves

Waves play an extremely important role in many areas of our lives.

Physics

Keywords

wave, wave types, sound wave, gravitational wave, electromagnetic wave, mechanical wave, longitudinal, transverse, frequency, amplitude, sound, wavelength, spread velocity, vibration, period of oscillation, polarizing filter, radio wave, microwave, light, visible light, ultraviolet radiation, infrared radiation, polarised wave, infrasound, ultrasound, antenna, gravitation, mechanics

Related items

### Longitudinal waves

• Longitudinal wave - The motion of the particles is parallel to the direction of wave propagation. Mechanical waves traveling through gases are always longitudinal.
• speaker - The speaker emits longitudinal sound waves. Sound, like any other wave, is characterized by wavelength, frequency, wave speed and amplitude.
• direction of wave propagation
• motion of particles

The simplest mechanical waves are sound waves that travel through various gases. The source of the sound causes the gas molecules to vibrate. Then the molecules that are already vibrating cause neighboring molecules to vibrate as well. This process is repeated, and this is how vibration propagates.

Mechanical waves traveling through gases are always longitudinal, that is, the direction of particle movement is parallel to that of wave propagation. This is because particles in the gas do not attract one another and thus shear forces are not exerted on them. A single particle can only cause particles that are in front of it to vibrate. Longitudinal waves cannot be polarized.

### Transverse waves

• Transverse wave - The motion of the particles is perpendicular to the direction of wave propagation.
• direction of wave propagation
• motion of particles

Mechanical waves traveling through solids or liquids can either be transverse or longitudinal.

Transverse waves are waves in which the displacement of the particles is perpendicular to the direction of wave propagation. When we pluck a guitar string, the wave travels along the string but the vibration is perpendicular to the movement of the wave.

If vibration takes place throughout the same plane, we say that the wave is linearly polarized.

### Complex waves - Water waves

• Water wave - These waves are longitudinal and transverse at the same time: the particles of water move in circles.

Most of the waves observed in nature are not purely transverse or longitudinal, just as transverse waves are not always polarized in a single plane.

These movements of particles in a certain medium usually occur at the same time. Any complex wave motion can be described as a combination of a longitudinal and one or more transverse waves. For example, when we look at waves on the water, the particles are moving not only up and down, but also backwards and forwards, so water waves can also be described as a combination of longitudinal and transverse waves.

The reason for this is that water is not a compressible medium, so the downward-moving particles do not compress the particles under them, but push them to the sides. Waves traveling through a solid medium (e.g. seismic waves) are even more complex.

### Polarization

• circularly polarized transverse wave - A combination of two transverse waves that are perpendicular to each other.
• linearly polarized transverse wave - A wave in which the particles travel in a single plane; their motion is perpendicular to the direction of wave propagation.
• polarizer - Waves become linearly polarized when they pass through this filter.
• perpendicular polarizer

An elliptically polarized wave is a composition of two transverse waves, but this wave can be circularly polarized in special cases.

A circularly polarized wave can be easily generated by tying one end of an elastic rope to a fan blade and keeping the rope stretched by pulling the other end.

To transform a circularly polarized wave into a linearly polarized wave, one needs a polariser. For mechanical waves, this polariser is a gap. Once the wave passes through this gap, it becomes linearly polarized. If another polariser, perpendicular to the first one, is placed in the path of the wave, the wave will not pass through it.

### Electromagnetic waves

• Electromagnetic dipole radiation - The changing electric field around the antenna induces a changing magnetic field, which, in turn, generates a changing electric field and this process is repeated infinitely.
• antenna - The charge distribution in it changes periodically, therefore the electric field formed around it also changes periodically.

Electromagnetic waves are not vibrations of a material medium. In fact, they do not need a medium to propagate, and they propagate the fastest through a vacuum.

They are generated as the changing electric field produces a changing magnetic field, which, in turn, generates another changing electric field and this process is repeated.

When electromagnetic waves are generated, there are no vibrating particles, so it is not easy to interpret polarization in this case. However, if we identify the direction of the vibration with the changing electric field intensity vector, electromagnetic waves are also considered transverse waves, so their polarization can be linear or more complex.

Natural light is a wave that is not polarized in a single plane, as it does not come from a single source. Numerous molecules or atoms generate it independently of one another, polarizing it in different planes. Natural light can be polarized with optical polarizing filters.

### Gravitational waves

• Gravitational wave - They can be generated, for example, by two stars orbiting around each other.

Gravitational waves are generated as a result of accelerating masses. Essentially, they are considered ripples in space-time. They result in the expansion and contraction of space-time at a given point. This can only be detected with very precise instruments, and only very large accelerating masses, such as the components of a binary star system orbiting around each other, can create significant gravitational waves that can be detected.

### Types of waves

• Source
• Mechanical
• Electromagnetic
• Gravitational
• Polarization
• Longitudinal
• Transverse
• Complex
• Frequency, wavelength
• Infrasound - It is generated by earthquakes but it is also emitted by whales and elephants. It has a frequency of 0 to 20 Hz.
• Audible sound - The frequency of sound waves audible to humans range from 20 to 20,000 Hz.
• Ultrasound - It is used by bats and dolphins; we use it in medicine for diagnostic imaging. It has a frequency higher than 20,000 Hz.
• Radio wave - [b]Long wave[/b] - wavelength: 1,000–2,000 m, frequency (Hz): 1.5×10⁵–3×10⁵ [b]Medium wave[/b] - wavelength: 150–600 m, frequency (Hz): 5×10⁵–2×10⁶ [b]Short wave[/b] - wavelength: 15–50 m, frequency (Hz): 6×10⁶–2×10⁷ [b]Ultra-short wave[/b] - wavelength: 1–15 m, frequency (Hz): 2×10⁷–3×10⁸ Radio waves are used by radios and radars.
• Microwave - wavelength: 1 m–0.03 mm, frequency (Hz): 3×10⁸–10¹³ It is used by mobile phones, Wi-Fi routers and microwave ovens.
• Infrared radiation - wavelength: 0.3–760 nm, frequency (Hz): 10¹²–3.9×10¹⁴ The Sun, the human body and heaters radiate heat in the form of infrared radiation too.
• Visible light - wavelength: 760–380 nm, frequency (Hz): 3.9×10¹⁴–7,8×10¹⁴ Light is also a type of electromagnetic wave.
• Ultraviolet radiation - wavelength: 380–10 nm, frequency (Hz): 7.8×10¹⁴–3×10¹⁶ An overexposure to UV rays coming from the Sun causes sunburn.
• X-radiation - wavelength: 1 nm–1 pm, frequency (Hz): 3×10¹⁶–3×10²⁰ An overexposure to X-rays from medical imaging can damage our cells.
• Gamma radiation - wavelength: 0.3 nm–30 fm, frequency (Hz): 10¹⁸–10²² Gamma rays, whether of cosmic origin or generated by nuclear reactions, are electromagnetic waves of the most destructive power.
• Other mechanical waves

Waves play an extremely important role in a great many areas of our lives. Sound and light are waves, as are earthquakes. Radio broadcasting, radar and laser are also based on waves.

Waves can be categorized by various properties. The most common categories are based on the medium through which the waves travel. They can also be grouped by polarization and frequency.

Depending on the medium, waves can be:

1) Mechanical waves (e.g. sound, ultrasound, seismic waves, water waves)

3) Gravitational waves

4) The functions that describe the quantum state of systems can also be considered waves; they are therefore also called wave functions.

### Animation

• Longitudinal wave - The motion of the particles is parallel to the direction of wave propagation. Mechanical waves traveling through gases are always longitudinal.
• speaker - The speaker emits longitudinal sound waves. Sound, like any other wave, is characterized by wavelength, frequency, wave speed and amplitude.
• direction of wave propagation
• motion of particles
• Transverse wave - The motion of the particles is perpendicular to the direction of wave propagation.
• direction of wave propagation
• motion of particles
• Water wave - These waves are longitudinal and transverse at the same time: the particles of water move in circles.
• circularly polarized transverse wave - A combination of two transverse waves that are perpendicular to each other.
• linearly polarized transverse wave - A wave in which the particles travel in a single plane; their motion is perpendicular to the direction of wave propagation.
• polarizer - Waves become linearly polarized when they pass through this filter.
• perpendicular polarizer
• Electromagnetic dipole radiation - The changing electric field around the antenna induces a changing magnetic field, which, in turn, generates a changing electric field and this process is repeated infinitely.
• antenna - The charge distribution in it changes periodically, therefore the electric field formed around it also changes periodically.
• Gravitational wave - They can be generated, for example, by two stars orbiting around each other.
• Source
• Mechanical
• Electromagnetic
• Gravitational
• Polarization
• Longitudinal
• Transverse
• Complex
• Frequency, wavelength
• Infrasound - It is generated by earthquakes but it is also emitted by whales and elephants. It has a frequency of 0 to 20 Hz.
• Audible sound - The frequency of sound waves audible to humans range from 20 to 20,000 Hz.
• Ultrasound - It is used by bats and dolphins; we use it in medicine for diagnostic imaging. It has a frequency higher than 20,000 Hz.
• Radio wave - [b]Long wave[/b] - wavelength: 1,000–2,000 m, frequency (Hz): 1.5×10⁵–3×10⁵ [b]Medium wave[/b] - wavelength: 150–600 m, frequency (Hz): 5×10⁵–2×10⁶ [b]Short wave[/b] - wavelength: 15–50 m, frequency (Hz): 6×10⁶–2×10⁷ [b]Ultra-short wave[/b] - wavelength: 1–15 m, frequency (Hz): 2×10⁷–3×10⁸ Radio waves are used by radios and radars.
• Microwave - wavelength: 1 m–0.03 mm, frequency (Hz): 3×10⁸–10¹³ It is used by mobile phones, Wi-Fi routers and microwave ovens.
• Infrared radiation - wavelength: 0.3–760 nm, frequency (Hz): 10¹²–3.9×10¹⁴ The Sun, the human body and heaters radiate heat in the form of infrared radiation too.
• Visible light - wavelength: 760–380 nm, frequency (Hz): 3.9×10¹⁴–7,8×10¹⁴ Light is also a type of electromagnetic wave.
• Ultraviolet radiation - wavelength: 380–10 nm, frequency (Hz): 7.8×10¹⁴–3×10¹⁶ An overexposure to UV rays coming from the Sun causes sunburn.
• X-radiation - wavelength: 1 nm–1 pm, frequency (Hz): 3×10¹⁶–3×10²⁰ An overexposure to X-rays from medical imaging can damage our cells.
• Gamma radiation - wavelength: 0.3 nm–30 fm, frequency (Hz): 10¹⁸–10²² Gamma rays, whether of cosmic origin or generated by nuclear reactions, are electromagnetic waves of the most destructive power.
• Other mechanical waves

### Narration

Waves play an extremely important role in a great many areas of our lives. Sound and light are waves, as are earthquakes. Radio broadcasting, radar and laser are also based on waves.

Waves can be categorized by various properties. The most common categories are based on the medium through which the waves travel. They can also be grouped by polarization and frequency.

Depending on the medium, waves can be mechanical waves, electromagnetic waves and gravitational waves. The functions that describe the quantum state of systems can also be considered waves; they are therefore also called wave functions.

The simplest mechanical waves are sound waves that travel through various gases. The source of the sound causes the gas molecules to vibrate. Then the molecules that are already vibrating cause neighboring molecules to vibrate as well. This process is repeated, and this is how vibration propagates.

Mechanical waves traveling through gases are always longitudinal, that is, the direction of particle movement is parallel to that of wave propagation. This is because particles in the gas do not attract one another and thus shear forces are not exerted on them. A single particle can only cause particles that are in front of it to vibrate. Longitudinal waves cannot be polarized.

Mechanical waves traveling through solids or liquids can either be transverse or longitudinal.

Transverse waves are waves in which the displacement of the particles is perpendicular to the direction of wave propagation. When we pluck a guitar string, the wave travels along the string but the vibration is perpendicular to the movement of the wave.

If vibration takes place throughout the same plane, we say that the wave is linearly polarized.

Most of the waves observed in nature are not purely transverse or longitudinal, just as transverse waves are not always polarized in a single plane.

These movements of particles in a certain medium usually occur at the same time. Any complex wave motion can be described as a combination of a longitudinal and one or more transverse waves. For example, when we look at waves on the water, the particles are moving not only up and down, but also backwards and forwards, so water waves can also be described as a combination of longitudinal and transverse waves.

The reason for this is that water is not a compressible medium, so the downward-moving particles do not compress the particles under them, but push them to the sides. Waves traveling through a solid medium (e.g. seismic waves) are even more complex.

An elliptically polarized wave is a composition of two transverse waves, but this wave can be circularly polarized in special cases.

A circularly polarized wave can be easily generated by tying one end of an elastic rope to a fan blade and keeping the rope stretched by pulling the other end.

To transform a circularly polarized wave into a linearly polarized wave, one needs a polariser. For mechanical waves, this polariser is a gap. Once the wave passes through this gap, it becomes linearly polarized. If another polariser, perpendicular to the first one, is placed in the path of the wave, the wave will not pass through it.

Electromagnetic waves are not vibrations of a material medium. In fact, they do not need a medium to propagate, and they propagate the fastest through a vacuum.

They are generated as the changing electric field produces a changing magnetic field, which, in turn, generates another changing electric field and this process is repeated.

When electromagnetic waves are generated, there are no vibrating particles, so it is not easy to interpret polarization in this case. However, if we identify the direction of the vibration with the changing electric field intensity vector, electromagnetic waves are also considered transverse waves, so their polarization can be linear or more complex.

Natural light is a wave that is not polarized in a single plane, as it does not come from a single source. Numerous molecules or atoms generate it independently of one another, polarizing it in different planes. Natural light can be polarized with optical polarizing filters.

Gravitational waves are generated as a result of accelerating masses. Essentially, they are considered ripples in space-time. They result in the expansion and contraction of space-time at a given point. This can only be detected with very precise instruments, and only very large accelerating masses, such as the components of a binary star system orbiting around each other, can create significant gravitational waves that can be detected.

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