Waves

Waves are a disturbance or vibration that travels throughout space-time and is followed by an energy transfer, as defined by physics. Waves motion transports energy from one location to another with no permanent shift of the medium’s particles — in other words, with no mass movement. Instead, they’re made up of vibrations or tremors that happen at nearly regular intervals.

At least two field quantities in the medium of the waves are engaged in physical waves. Waves can be regular, in which case the quantities fluctuate at a set frequency around an equilibrium value. A travelling wave occurs when the whole waveform moves in one direction; a standing wave occurs when two superimposed periodic waves move in opposite directions. The vibration amplitude in a standing wave features nulls at some points when the wave amplitude seems reduced or even zero.

Property of Waves:

Following are the main characteristics or properties of waves:

1.     Frequency:

Frequency is the number of waves that travel through a given spot in a given amount of time. The higher the frequency, the closer the waves are to each other and the more energy the waves carry.

The period of the wave is inversely proportional to its frequency.

Frequency=1/period

f = 1/T

             A hertz is a unit of measurement for waves (Hz).

                 Amplitude:

The length between a line through the centre of a wave and a peak or dip is measured in amplitude. The stronger the force that creates a wave, the larger the wave’s amplitude and the more energy it carries.

The crest of a transverse wave is its highest point, while the trough is its lowest.

The amplitude of a transverse wave is proportional to its height.

Sounds with more amplitude are louder, and light with more amplitude is brighter.

3.     Wavelength:

The distance between the crests of one wave and the crests of the following wave is measured in wavelength. A shorter wavelength and more energy are produced at a higher frequency.

A wave’s wavelength is defined as the distance between two consecutive crests or troughs.

•     The highest point of a wave is referred to as the crest.
•     The lowest points of a wave are referred to as troughs.
•     A sine curve represents the shape of a wave, and it describes simple harmonic motion, which is the motion of the pendulum.

4.     Speed:

The distance travelled by waves in a given time is referred to as speed.

The wave and the nature of the medium determine the speed of waves.

The speed of a wave changes as it enters a different medium. In different media, waves travel at different speeds.

Types of Waves:

Types of waves are broadly classified into three categories, they are as follows:

•     Mechanical Waves
•     Electromagnetic Waves
•     Matter Waves

We will discuss each wave type in detail:

1.     Mechanical Waves – Due to the repetitive periodic movement of the medium’s particles about their mean positions, these mechanical waves serve as the propagation of a disturbance across the material medium, with the disturbance being passed from one particle to the next. They are further divided into two types:
2. a)     Longitudinal Waves- 

When the particles in the medium fluctuate about their mean positions in the wave’s propagation direction, the wave is called longitudinal. For a longitudinal wave, the vibration of the medium particles is in the direction of the flow. A longitudinal wave persists in the form of rarefaction and compression, which is compression in the same direction as the waves and extends in the same direction as the waves. For a longitudinal wave, the density and pressure tend to be highest at compression points and lowest at rarefaction points. In gases, only longitudinal waves may propagate. Compression waves are another name for longitudinal waves.

1. b)   Transverse Waves-

Transverse waves are disturbances in a medium in which the medium’s particles fluctuate about their mean positions at right angles to the wave’s propagation direction. This motion occurs in a cyclical rhythm and continues indefinitely. A transverse wave propagates in a medium with particles vibrating in a direction perpendicular to the wave’s propagation direction. There is the production of a trough and crest, as well as the possibility of polarisation of a transverse wave. Ripples on the water’s surface, string vibrations, and other transverse waves are examples.

     Electromagnetic Waves- Electromagnetic waves are created when an electric field and a magnetic field are connected together. These waves are perpendicular to both the electric and magnetic fields, and they are also perpendicular to each other. Electromagnetic waves can be visible when there are periodic disturbances in the magnetic and electric fields, and these waves will have a frequency that falls within the electromagnetic spectrum’s range. The propagation of electromagnetic waves does not need the use of a medium. These waves can also be polarised and are transverse. Microwaves and X-rays are a few examples of electromagnetic waves.

     Matter Waves- Matter waves, also known as the De Broglie waves illustrate the wave nature of all matter, including human bodies, atoms, and other subatomic particles. It has been established that matter waves are extremely small, and that these waves are generated by electrons and particles. The De Broglie equations are a set of equations that propose the dual nature of matter. These waves’s frequency is precisely proportional to their kinetic energy.

     Surface waves-  Surface waves have both a mechanical and an electromagnetic component to them. An ocean wave is the best example for surface waves, which are also known as Rayleigh waves.

     Elastic Waves- Elastic waves are created by naturally elastomeric bodies. The vibratory motion of the particles is caused by the elastic body, and the vibratory motion is what creates the elastic wave. In the case of an elastic wave, the particles always tend to return to their original places while setting in wave motion, and this also propagates in the medium of viscoelastic. Elastodynamics is the scientific study of these elastic waves.

 Conclusion-

Wind blowing across the ocean surface is the primary cause of waves in the ocean. The substance or material that conveys a mechanical wave is referred to as the “medium.” The fact that waves transmit energy rather than substance is one of the most fundamental things to understand about them. This distinguishes them from other physics phenomena. Microwaves and radio waves are examples of invisible waves.