Light is amazing ~ some factoids

Light is amazing ~ some factoids

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Treat Everyone Equal

Halifax, Nova Scotia

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@bigdogg said
πŸ˜‚

I'm stealing this.

Edit. Found this... It's hilarious.

https://www.michaelhartzell.com/blog/dopeler-effect-the-tendency-of-stupid-ideas-to-seem-smarter
You're not actually stealing it if it is on the internet, just someone got to it first is all. πŸ™‚

Then they biatch about plagiarism when they do it themselves. πŸ™‚

It is quite amusing though, one of the few links I have went to that the gooster has put up. πŸ™‚


-VR

Misfit Queen

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@moonbus said
For anyone who cares to listen:

Einstein's fundamental insight is this: the speed of light does not accumulate, unlike the speed of a bullet. For example, if a bullet exits the muzzle of a gun at 200 mph, and the gun is pointing forwards on a freight train moving at 100 mph, then the total speed of the bullet is 300 mph (minus some air friction, of course). Whereas, if you ...[text shortened]... eed the speed of the train itself, it'll be 'stuck', as it were, on (or in) the light source itself.
Only to an observer off the train. One not going "c".

If you were on the train you'd see the "headlights" go forward like they do on a car, because to you, it seems you are stationary and the universe is going past you at "c".

This is the magic of "relativity".

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@suzianne said

If you were on the train you'd see the "headlights" go forward like they do on a car, because to you, it seems you are stationary and the universe is going past you at "c".

This is the magic of "relativity".
No. If you are on a train going at c and you turn on the headlights, no light from the train's headlights going in the same direction as the train can go faster than the train is already going, because the speed of light is not cumulative.

Misfit Queen

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@moonbus said
No. If you are on a train going at c and you turn on the headlights, no light from the train's headlights going in the same direction as the train can go faster than the train is already going, because the speed of light is not cumulative.
IF you are an observer NOT on the train.

If you are an observer on the front of the train, you would see a headlight normally.

https://www.tiktok.com/@sonde2007/video/7301155495203687722

This is what relativity means.


Then there's this.

(I love this guy. πŸ™‚ )

I know it is a longer video, but the bottom line is that, yes, c is c, but what observers see is relative to that observer.

As I said, this is the magic of relativity.

K
within reason

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@suzianne said
IF you are an observer NOT on the train.

If you are an observer on the front of the train, you would see a headlight normally.

https://www.tiktok.com/@sonde2007/video/7301155495203687722

This is what relativity means.


Then there's this.
[youtube]ACUuFg9Y9dY[/youtube]
(I love this guy. πŸ™‚ )

I know it is a longer video, but the bottom line is that, yes, c is ...[text shortened]... at observers see is relative to that observer.

As I said, this is the magic of relativity.
"If you are an observer on the front of the train, you would see a headlight normally"

The train is already traveling at c. So in order for an observer on that train to "see a headlight normally" photons from the headlights would have to be traveling at twice the speed of light.

But if that train was traveling at 99.9999% the speed of light then yes, photons emanating from the headlights could be observed traveling away from the train at c.

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@kilroy70 said
"If you are an observer on the front of the train, you would see a headlight normally"

The train is already traveling at c. So in order for an observer on that train to "see a headlight normally" photons from the headlights would have to be traveling at twice the speed of light.

But if that train was traveling at 99.9999% the speed of light then yes, photons emanating from the headlights could be observed traveling away from the train at c.
Relativity seems to be a misunderstood term, I guess.

Everything is relative to the observer's frame of reference.

An observer ON the train is hard pressed to tell if the train is moving, or if the environs is moving. As far as he can tell, the train is traveling at 0, especially at 0 acceleration. Add the speed of the headlight, c, and 0 + c = c.

I'm definitely not going to talk about time dilation in this environment, since it is even harder to grasp. Lorentz-Fitzgerald transformations, etc.

K
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@suzianne said
Relativity seems to be a misunderstood term, I guess.

Everything is relative to the observer's frame of reference.

An observer ON the train is hard pressed to tell if the train is moving, or if the environs is moving. As far as he can tell, the train is traveling at 0, especially at 0 acceleration. Add the speed of the headlight, c, and 0 + c = c.

I'm definitely n ...[text shortened]... ion in this environment, since it is even harder to grasp. Lorentz-Fitzgerald transformations, etc.
He can't be a very observant observer if he thinks his speed is zero while positioned on a train traveling at the speed of light.
He might be tempted to step outside for a smoke, or make some other egregious error in judgment.

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If the speed of light is always constant, then it must also be assumed that it has no acceleration properties. It must reach its speed instantly, at the very moment of its creation. There is no time for acceleration? And God said, “Let there be light,” and there was light.

Also, if light is energy, and its speed is always constant, then, using a philosophical interpretation, it can be surmised that it is immortal once created, since it will never exhaust itself? Unless we can consider light changing into matter, and vice versa, as being the end and the beginning of light energy. In which case, it's an immortal never-ending cycle of the nature of energy and matter within a universal container.

But then, is the universal container itself, immortal?

A departing and thoughtful question: Does light ever reach the point it's headed towards? Light, if not restricted directionality, is said to radiate in a trajectory of a full 360 degrees.

In relation to its constant speed, it can be assumed that, using a fixed point for the emission of light, and just as an example for two relative points, at the 180 degrees point, light will be traveling in two complete opposite directions, both at the speed of light. Therefore, it's not unreasonable to assume that light may be traveling at twice its constant speed, if we take into consideration the two opposite directions.

It's a matter of geometry that enlightens the thought on speed. The center of a circle is the point of the emitting light, and the radius of the circle is light reaching one side of the circle, and the other radius at the opposing 180 degrees is light reaching the opposing side of the circle. In other words, the diameter of a circle represents light traveling at twice its constant speed along that line.

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@pettytalk said
If the speed of light is always constant, then it must also be assumed that it has no acceleration properties. It must reach its speed instantly, at the very moment of its creation. There is no time for acceleration? And God said, “Let there be light,” and there was light.

Also, if light is energy, and its speed is always constant, then, using a philosophical interpretat ...[text shortened]... ds, the diameter of a circle represents light traveling at twice its constant speed along that line.
My post on page 1:

A few years ago Stamford University slowed light down to 27mph.
Then Harvard slowed light down to zero.

Fighting for men’s

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@pettytalk said
If the speed of light is always constant, then it must also be assumed that it has no acceleration properties. It must reach its speed instantly, at the very moment of its creation. There is no time for acceleration? And God said, “Let there be light,” and there was light.

Also, if light is energy, and its speed is always constant, then, using a philosophical interpretat ...[text shortened]... ds, the diameter of a circle represents light traveling at twice its constant speed along that line.
Post your source Sir.

How many times in your life do you need to be told.

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@pettytalk said
If the speed of light is always constant, then it must also be assumed that it has no acceleration properties. It must reach its speed instantly, at the very moment of its creation. There is no time for acceleration? And God said, “Let there be light,” and there was light.

Also, if light is energy, and its speed is always constant, then, using a philosophical interpretat ...[text shortened]... ds, the diameter of a circle represents light traveling at twice its constant speed along that line.
That word 'assumed' leads to all kinds of bad decisions.

Treat Everyone Equal

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@suzianne said
That word 'assumed' leads to all kinds of bad decisions.
I had assumed just that! πŸ™‚

-VR

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@divegeester said
Post your source Sir.

How many times in your life do you need to be told.
You got to be kidding! Do you want me to link my brain on the screen? It's satire.

Being dyslectic is the least of your problems.

Treat Everyone Equal

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@divegeester said
Post your source Sir.

How many times in your life do you need to be told.
There is not rule saying you must Post your Source!

Ignore this geester! πŸ™‚

-VR

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@suzianne said
That word 'assumed' leads to all kinds of bad decisions.
They danced the light fandango
Turned cartwheels cross the floor.