# Waves. Mechanical and electromagnetic waves

## Would you like to know more about waves, their properties and types?

The online wave simulations on this page teach you in a practical way how waves are generated, how they propagate and the most important types.

Waves are disturbances that propagate through space and time, carrying energy with no net transport of matter. They are fundamental phenomena found in many branches of physics, such as optics, acoustics, electromagnetism and mechanics. Waves can be classified into two main categories: mechanical waves and electromagnetic waves.

Mechanical waves require a material medium to propagate. For example, sound waves are mechanical waves that propagate through the vibration of particles in a medium, such as air, water or solids. Other examples of mechanical waves include waves on a taut string, seismic waves on Earth, and waves in the ocean.

Electromagnetic waves, on the other hand, do not require a material medium to propagate and can move through a vacuum. These waves are composed of oscillating electric and magnetic fields that propagate perpendicular to each other. Visible light, radio waves, X-rays and microwaves are examples of electromagnetic waves.

Waves are described by several characteristics. Wave amplitude is the maximum distance that particles move from their equilibrium position. Wavelength is the distance between two equivalent points on the wave, such as two consecutive crests or two consecutive valleys. Frequency is the number of oscillations that occur per unit time and is measured in hertz (Hz).

## Introduction. Water, sound and light

Make waves with a dripping faucet, an audio speaker or a laser! Adjust the frequency and amplitude, and observe the effects. Listen to the sound produced by the speaker and find out what determines the color of the light.

## Plane and circular waves I

Plane waves and circular waves can be generated in a wave trough, depending on the type of generator used. Similar to light rays, plane waves do not diverge.

## Plane and circular waves II

This simulation represents more realistically plane and circular waves in a wave trough. It explains why the waves are visible on a screen through a back projection system.

## Waves in water

If a stone is thrown into a still pool of water, concentric waves are created and spread out around it. If the waves are generated next to a floating object, it can be observed that the object does not move and will only vibrate up and down. This is because, although the wave is displaced, the medium (water in this case) only vibrates vertically.

## Sound waves

With this sound wave simulation we can explain how different sounds are modeled, described and produced. Design different sound wave models and determine the speed, frequency, period and wavelength.

## Wave propagation

A wave transmits energy through a medium. The medium only vibrates, but does not move. Moreover, there are waves, such as electromagnetic waves, that do not need a medium.