Does the color of a laser affect the velocity of the light wave projected by the laser? Why or Why not?

Question

Lasers used from surgery to supermarket checkout scanners

Answer 1

As far as I Know, in empty space light always travels at the same speed. Now it can change speeds depending what it is traveling through. Thats why things are out of place when obderved from above water.

Answer 2

In a vacuum, all electromagnetic radiation travels at the same speed - the speed of light. But when light travels through other mediums, like air, water, etc, each frequency travels at a slightly different speed. You can see that in visible light as it passes through a prism - that is why different colors refract at different angles - but actually it happens for all frequencies of electromagnetic radiation. The nature of electromagnetic radiation does not make an exception for us just because we are able to see certain frequencies.

The reason this is true is actually quite complicated and involves quite sophisticated concepts of quantum mechanics. But basically it comes down to the fact that light (photons)  gets absorbed into the electron structures of atoms and molecules and then reemitted as light, and while it is absorbed, it is not moving. Of course this is happening very VERY fast. And the average speed usually ends up being a little slower than lightspeed, and varies according to the energy, or frequency, of the light with the highest frequencies slowing the most.

Answer 3

Joel is right. Frequency does not affect velocity. If it did, then wavelength would be affected inversely to the manner in which frequency was, and that is not the case. We can tell it is not the case from observation; if they did, the arrival of the electromagnetic spectrum at any given point would be separated in the same way that a prism separates visible light by its wavelength.

As an aside, the only kinds of transmissions that are slowed when passing through a given medium are those sorts of transmissions that require that medium for their transferrence to occur. Hence, sound waves (which depend on the vibration of particles) change speed based on the medium they are transferred through. Light does not require the existence of a transfer medium, and cannot be slowed. It can be stopped, however. For that to occur I would need to stand up, turn my computer off, and hit the light switch to go to bed. :)

Answer 4

No.  The speed of light is a constant in any given medium (for that matter, this applies to any electromagnetic radiation including radio, xray, infrared, etc).  The frequency does not affect the velocity of the light.