Progressive waves

A wave that travels continuously in the medium from one point to another in the same direction without any change in its amplitude is termed progressive. When the particles of a medium vibrate simply harmonically around their mean positions throughout the propagation of a wave through it, the wave is said to be a plane progressive harmonic wave. 

Waves help in the movement of energy without requiring the transport of stuff. Waves are disturbances that transmit energy from one location to another without carrying substance through a medium. To transfer energy from one spot in a medium to another, waves require oscillating or vibrating sources. These study material notes on progressive waves will help you understand the concept better.

A progressive wave is a wave that progresses from one point A in the medium to another point B in the medium. A travelling wave, also known as a progressive wave, is a wave that travels in the same direction in the same medium without changing. Furthermore, there are two types of progressive waves: transverse and longitudinal waves.

Plane Progressive Harmonic Wave

The particles in a medium tend to oscillate harmonically around their mean locations throughout the transmission of a wave. In this instance, a wave is a plane progressive harmonic wave.

Simple Harmonic Progressive Wave

This waveform continues to move in the same direction without changing shape. Furthermore, the medium’s particles move harmonically around their mean location, with the same amplitude and period.

Characteristics of SHM Wave

• While the wave travels through a medium, all particles or components of the medium display SHM
• As they vibrate, all particles keep the same amplitude
• The medium is used to conduct energy
• The entire number of particles vibrates at the same time.

The wavelength of Progressive Wave

For Progressive waves, the wavelength ‘’ is the distance measured between two successive points of the same phase at a given time. This is twice the distance measured between two consecutive nodes or antinodes in the case of a stationary wave. The propagation constant is denoted by the letter ‘k.’ The radian per metre, or rad m-1, is the SI unit.

 k=2/

Frequency and Period of Progressive Wave

The period ‘T’ of a wave oscillation is the time for each component of the medium to complete one full oscillation. The following relationship connects this to ‘’ or angular frequency.

 =2/T

The wave frequency ‘v’ is expressed as 1/T and is connected to angular frequency as follows:

 v=/2

Alternatively, it may be described as the number of oscillations per unit time in a string element as the wave travels through it. In most cases, this is computed in Hertz.

The Intensity of Progressive Wave

We get a pleasant sensation in the ear when we hear the sound of a violin and the instrument flute or harmonium, but we get an unpleasant feeling when we hear the sound of a pistol, a horn, a motor car, and so on.

The loudness of a sound is determined by the strength of the sound wave and the ear’s sensitivity.

The intensity is commonly defined as the amount of energy traversing per unit area per unit time in a direction perpendicular to the wave’s propagation path.

W m–2 is the unit of measurement for intensity.

Progressive Wave – Important Points

• Each particle in the medium produces a vibration centred on its mean location. The disruption spreads from one particle to the next
• The medium’s particles vibrate with equal amplitude around their mean locations.
• Each particle, or we may say, each subsequent particle of the medium, moves in the same direction as its predecessor along the wave’s propagation path, albeit at a later period
• In most cases, no particle stays in the rest position indefinitely. The particles are temporarily at rest at extreme locations twice throughout each vibration. Various particles arrive at different positions at different times

• An energy transfer also occurs across the medium in the direction of Progressive waves propagation.
• When particles travel through the mean location, they all have the same maximum velocity
• The displacement of the particle’s velocity and acceleration are the same when separated by the equation m, where m is an integer

Conclusion 

Regardless of the medium, the amplitude of the Progressive waves remains constant as it travels in the same direction throughout time. A transverse or a longitudinal progressive wave might be used. Consider a plane with simple harmonic motion going down the X-axis from its O origin. Counting backward from the moment of creation, we see that the particle at this origin is simply moving through the mean position in a positive direction.