Brian Cox has a great style, is smart and knowledgeable an excellent to listen to.
Einstein was one of the best minds ever, his contribution’s immeasurable.
The Speed Of Light ??
- Thread starter billt460
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Einstein was one of the best minds ever, his contribution’s immeasurable.
For those of you with electrical knowledge. How about the speed of electricity through a high tension line? I'm talking about the big, high voltage, high tension power lines that stretch for miles across the country. That are carrying hundreds of thousands of volts.
I've heard both. It is at the speed of light, or else very close to it. And also that it is much slower. The same with it traveling either over, or through the line itself.
I've heard both. It is at the speed of light, or else very close to it. And also that it is much slower. The same with it traveling either over, or through the line itself.
Well yall are clearly more learned than me......but I interpret constant, as constant, unchanging, relentless.
A little itty bitty bit different, is a difference. And, the faster and farther you go, the larger the error. If it is slower in some cases, i may also be reasonable to assume it might be even slower in other cases, or maybe even faster.
So I wonder if this has to do with the measurement technique, or reality?
Not that fast. But comparing to photons in a vacuum is not really proper.
Read this: https://electronics.stackexchange.c...trons-actually-flow-when-a-voltage-is-applied
But that's what people do. Most everything that moves exceptionally fast, is compared to, "the speed of light". And because there is nothing faster, (at least nothing that we currently know of), it becomes a sort of standard that other things are compared to. Lightning moving from the clouds to the ground, current through or over a wire, etc.
Well, that little itty, bitty, bit only applies when it’s going through something like water, or, in this case, coke, so, it’s irrelevant in the big scheme of things.
The speed is a constant in a vacuum - which means all of interplanetary space, interstellar space, and across the universe.
Your objection is largely irrelevant, because the applicability is for terrestrial observation, through translucent media, and where light speed matters, in the universe writ large, it is, in fact, constant.
I would recommend picking up a couple of good books on the topic - one of my favorites is the now Classic Stephen Hawking “A Brief History of Time.” Professor Hawking explains Relativity and Quantum Mechanics in a clear, accessible manner.
MolaKule
Staff member
Any object transparent to light has an index of refraction "n." The velocity of light passing through any object with an index of refraction n is v = c/n. Here, c is the velocity of light in a vacuum.
A further explanation is given below.
https://gurumuda.net/physics/speed-of-light-in-different-mediums.htm
https://micro.magnet.fsu.edu/primer/java/speedoflight/index.html
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MolaKule
Staff member
"The drift velocity [of a current charge, an electron] in a 2 mm diameter copper wire in 1 ampere current is approximately 8 cm per hour. "
http://amasci.com/miscon/speed.html
gives another meaning to miles per hour
So they don't really "move".... They more or less bump into one another? A bit like a loose length of rope, and you give one end a hard shake. The "wave" of rope travels down its length very quickly, but the rope itself doesn't go anywhere? A bit like that?
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If I remember, radio waves move at, or very close to the speed of light. During the Apollo Moon missions, the time it took for the radio waves, (voice transmissions), had about a 1-1/2 second lag, from when they were transmitted, to when we received them.
The Moon is 240,000 miles from Earth. So at 186,000 miles per second, that proves out.
The Moon is 240,000 miles from Earth. So at 186,000 miles per second, that proves out.
This is true because your experience is dependent on your reference frame. Different frames of reference have different experiences. For anything with no rest mass (light does have relativistic mass do to its energy and momentum), you MUST necessarily travel at the speed of light in vacuum regardless of the motion of the source of light.
The only difference between radio waves and photons of light is their wavelength - they are along with gamma rays, x-rays, infrared, etc all the same thing, part of the electromagnetic spectrum.
So the difference, has to do with refraction correct? If i am understanding this correctly.
Radio waves are light.
Just a different part of the spectrum than the light you see with your eyes, so, not “very close” but, exactly the speed of light between Earth and Moon.
They are both expressions of electromagnetic energy. Exhibit properties of waves and particles and we are back to 1 OP in this thread.
What portion of this video is wrong?
This will open up some thought patterns
