OK I was told that waves travel through matter...right? Well then in space there is no matter and how does light travel to earth? With no matter then it shouldn't right?
2007-05-23 07:04:38 · 6 answers · asked by CHIQUITA 2 in Science & Mathematics ➔ Physics
Light is actually composed of tiny "particles" called photons which can move through a vacuum. Photons also have many wave-like properties, that's where the term "light waves" comes from.
2007-05-23 07:09:29 · answer #1 · answered by Nature Boy 6 · 1⤊ 0⤋
That's why light is so confusing to scientists. It behaves like a wave. But it also behaves like particles. It can travel through a vaccum, for instance, but its speed is also affected by different mediums. Particle and wave characteristics. They call it the wave/particle duality of light.
2007-05-23 07:37:22 · answer #2 · answered by Mike 3 · 0⤊ 1⤋
light consists of eletromagnetic waves which can travel through vaccum or transparent medium.
Mechanical waves like sound, surface wavesetc . require a medium for their propagation, waves on a string as well.
2007-05-23 07:23:45 · answer #3 · answered by Anonymous · 1⤊ 0⤋
Light has no charge at all. It consists only of electric and magnetic field, each endlessly recreating the other as the pair zip off through empty space at the speed of light.
The fact that light waves can travel in vacuum, and don't need any material to carry them, was disturbing to the physicists who first studied light in detail. They expected to find a fluid-like aether, a substance that was the carrier of electromagnetic waves. Instead, they found that those waves travel through truly empty space. One thing led to another, and soon Einstein proposed that the speed of light was profoundly special and that space and time were interrelated by way of that speed of light.
Let's approach it this way. Light is actually a really complicated ‘thing’ to explain. There’s two ways to think about light. Light can be treated like a particle or a wave.
First, let’s think about light as a particle called a photon. So when someone refers to the speed of light, it is the speed of the photon and it travels at speed c in vacuum. Now in different material, photons seem to travel at different speeds. These materials are also made out of particles called atoms. As the photon goes through the material, it interacts with the atoms and has several different results, such as absorption and re-emission, and scattering. In the absorption and re-emission process, the photon is taken in by the atom and, after some time, is released by the atom. In the scattering process, the photon’s path changes because it collides with atoms. So because of these processes, the time that the photon takes to pass through the material becomes longer compared to vacuum. So this is why it appears that the light travels at a speed less than c. The actual speed of the photon is always c. The ratio of the speed of light in a material to the speed of light in vacuum is defined as n, the refractive index. For example, water has a refractive index of 1.33 so light will travel at c/1.33 in water.
Recently, researchers have been able to ‘control’ the speed of light. To understand this, you have to look at light in a different way. Here, think about light as a wave, similar to waves in the ocean. The speed of each ocean wave is dependent on the wavelength of the wave (distance from crest to crest) because of a phenomenon called dispersion. These waves typically travel in groups and the waves in the middle of the group are the largest. This group as a whole moves at a velocity called the group velocity. This is similar with light. The individual waves traveling at different velocities add up to form a group, which is also known as a pulse. Researchers are able to slow down the group velocity of this pulse by using a laser beam to create a region in the material with large dispersion for certain wavelengths centered on the pulse wavelength, causing the pulse of light to travel slower. The technique they use is called electromagnetically-induced transparency (EIT) and researchers have actually even been able to stop light for a short period of time.
2007-05-23 07:09:40 · answer #4 · answered by ? 6 · 0⤊ 2⤋
Light will travel through space and non opaque glass . u are trying to make it too complicated .
2007-05-23 08:38:11 · answer #5 · answered by JOHNNIE B 7 · 1⤊ 0⤋
Electromagnetic waves do not require matter,in fact That would slow them down..
2007-05-23 07:21:57 · answer #6 · answered by confused 3 · 1⤊ 0⤋