Transverse waves oscillate perpendicular to the direction of propagation.
In the field of physics , a wave is a periodic movement whose propagation can occur in a vacuum or in a physical medium. Transversal , on the other hand, is an adjective that refers to that which moves away from the straight direction, that is crossed perpendicularly or that is crossed.
A transverse wave , in this framework, is one that presents a vector magnitude with oscillations in a direction perpendicular to the direction of propagation . This characteristic allows them to be differentiated from longitudinal waves , which oscillate in the same direction as the movement of the wave.
To understand the notion of transverse wave, it is essential to remember that the propagation of waves in a medium is linked to the vibration they cause in the particles of the medium in question. When the direction of propagation is perpendicular to the direction in which these particles vibrate, it is a transverse wave. On the contrary, if the direction of propagation is equal to the direction in which the vibration of the particles of the medium occurs, the wave is longitudinal.
Examples of transverse waves
Electromagnetic waves , for example, are transverse waves. Just like the waves that are generated on the surface of the water if we throw a blunt object, to mention another case.
Suppose we throw a stone into a lake and it falls near where a buoy floats. The direction of the vibration that occurs on the surface is perpendicular to the direction of the wave displacement. The buoy, meanwhile, rises and falls according to the arrival of the wave fronts, which advance horizontally. The action, in short, gave rise to the appearance of transverse waves.
Transverse waves differ from longitudinal waves.
The rope case
There is a concept that is generally known as transverse waves in a rope and focuses precisely on the wave movement that propagates in a rope that is subjected to tension. One of the objectives that arise in problems of this type, in the field of physics, is to find out the speed at which waves propagate, and for that it is necessary to find the appropriate formula.
To explain this topic we will see an example below in which we will stop at each of the variables and finally arrive at the equation that allows us to calculate the speed of propagation of transverse waves on a rope. Take for example a rope with a certain tension, which we will represent with the variable T. When it is in balance, we can say that the line it forms is straight .
If, however, we move an element with a length dx from a point of which we know its position on the X axis and we do so by a magnitude ψ (the twenty-third Greek letter, psi ) taking its equilibrium position as a reference. To calculate the acceleration of the element we must apply Newton's second law , also known as the fundamental law of dynamics :
«the movement changes directly proportional to the force that is printed and does so in accordance with the straight line on which it is printed».
The tension is equal to the force that the left side of the rope exerts on the same side of the element, and at this point the direction is tangent to the rope, giving rise to an angle that we call α . The same can be said of the right side, with the difference that the angle formed is called α» . Since the element moves vertically, the equation we need to solve the problem is the following: velocity = √tension / linear density.