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pilebaina: 4 months ago

Do all the lights travel at the same speed? Or the amount of voltage is involved in this?

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Answer 1

ClaraListensprechen: 4 months ago | Last edited at 9:06PM on 2/20/2013

Not all light travels at the same speed. The rate of speed cited in other answers here is the speed of light in an absolute vacuum. In the presence of air, or dust, it slows down or is blocked altogether.

Refraction happens when a clear substance slows down light to the point where it separates into an array of different frequencies, which you see as a rainbow.

Red is the slowest frequency in the light spectrum, which is why astronomers rely on a "red shift" to determine if a planet is or is not receding. The redder the shift, the further away it has traveled.

The red shift in light is akin to the dopplar effect in sound.

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DrBrian: 4 months ago

Once again we agree to disagree! The speed of light is constant - irrespectve of what color we are talking about. All you say is correct in that the SPECTRUM of galaxies and stars is more spread out the further away the source, and YES that is how we kow galaxies are speeding away from us. BUT the speed of light is constant. Unchanging. Always. You are confusing distance with speed. A light year is a distance, not a time interval. All red shift does is confim our Universe is getting bigger - and at an increasing rate.

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ClaraListensprechen: 4 months ago

The speed of light is a constant in a vacuum. A vacuum is required for the speed of light to be constant.

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DrBrian: 4 months ago

The speed of light is absolute and immutable - the medium through which it is travelling has no effect on the spread of colors seen in a spectrum. The ratio of colors is the same whatever medium they are passing through. Red shift is a function of the distance and speed of receding galaxies and it is the recession that spreads out the spectrum towards red. The light and the colors in that light are still all belting along at the same, constant immutable speed. We only know this because the light reaching us from those galaxies is travelling at a known and constant speed. This light is travelling to us through the vacuum of space.

In physics (especially astrophysics), redshift happens when light seen coming from an object that is moving away is proportionally increased in wavelength, or shifted to the red end of the spectrum. More generally, when an observer detects electromagnetic radiation outside the visible spectrum, "redder" amounts to a technical shorthand for "increase in electromagnetic wavelength" — which also implies lower frequency and photon energy in accord with, respectively, the wave and quantum theories of light.

Redshifts are attributable to the Doppler effect, familiar in the changes in the apparent pitches of sirens and frequency of the sound waves emitted by speeding vehicles; an observed redshift due to the Doppler effect occurs whenever a light source moves away from an observer. Cosmological redshift is seen due to the expansion of the universe, and sufficiently distant light sources (generally more than a few million light years away) show redshift corresponding to the rate of increase of their distance from Earth.

HOWEVER - the speed of light HAS to remain constant. You ARE seeing a dopplar effect, but you are seeing a shift in wavelength, not speed!

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Answer 2

tt9400: 4 months ago via Android

light travels at the same speed

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Answer 3

caluvox: 4 months ago

All light moves at the same rate, this is 188,000 miles per second. The only thing effected by the power input is brilliancy.

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DrBrian: 4 months ago

YES - this is the best answer to the original question. You have my "Helpful" tick of approval....

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caluvox: 4 months ago

Thank you Dr.! :)

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Answer 4

aramsau23: 4 months ago

all light travels at the same speed regardless of what color the light is and voltage has absolutely nothing to do with it

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