Which type of wave is a light wave?
Electromagnetic waves are made of oscillating magnetic and electric fields and, like all waves, they carry energy. There are many types of electromagnetic waves. From lowest energy to highest energy (red to blue) there are radio waves, microwaves, infrared, visible light, ultraviolet, x-rays and gamma rays.
Light behaves as a wave - it undergoes reflection, refraction, and diffraction just like any wave would. Yet there is still more reason to believe in the wavelike nature of light. Continue with Lesson 1 to learn about more behaviors that could never be explained by a strictly particle-view of light.
- Quantum mechanics tells us that light can behave simultaneously as a particle or a wave. When UV light hits a metal surface, it causes an emission of electrons. Albert Einstein explained this "photoelectric" effect by proposing that light – thought to only be a wave – is also a stream of particles.
- One important thing to know about light is that it travels and behaves as waves. Light also has the character of a particle, but we're going to just look at some basic stuff about light as a wave. That means light can travel almost eight times around the Earth in a second.
- Einstein called these energy packets photons, and these are now recognised as a fundamental particle. Visible light is carried by photons, and so are all the other kinds of electromagnetic radiation like X-rays, microwaves and radio waves. In other words, light is a particle.
Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. The term vibration is precisely used to describe mechanical oscillation.
- One complete cycle of repetitive to and fro motion, from one extreme (maximum or minimum) to another (minimum or maximum) and back.
- A single oscillation in physics means going through one complete cycle. However the term oscillation is preferred over the term cycles when cycles are rapidly occurring. The rate at which cycles are occurring through some unit of time is called frequency.
- In mechanics and physics, simple harmonic motion is a special type of periodic motion or oscillation motion where the restoring force is directly proportional to the displacement and acts in the direction opposite to that of displacement.
Light is a disturbance of electric and magnetic fields that travels in the form of a wave. The speed of the light wave equals the frequency times the wavelength.
- Now that the dual nature of light as "both a particle and a wave" has been proved, its essential theory was further evolved from electromagnetics into quantum mechanics. Einstein believed light is a particle (photon) and the flow of photons is a wave.
- Electromagnetic waves are made of oscillating magnetic and electric fields and, like all waves, they carry energy. There are many types of electromagnetic waves. From lowest energy to highest energy (red to blue) there are radio waves, microwaves, infrared, visible light, ultraviolet, x-rays and gamma rays.
- Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space. This proved that radio waves were a form of light!
Updated: 23rd September 2018