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Hang on tight : Speed of LIGHT!

Something else I was wondering... if you were driving along at night, at the speed of light with your headlights on... would you be able to see where you were going?

If you're referring to a bike, then it's called "out-riding" your light. But it doesn't mean you're riding faster than the speed of light. It just means that you're riding faster than you can react due to your field of vision.
 
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Not until you reach Alpha Centauri - and then you would have to stop and ask the Robinsons for directions...



My only hope is that they have one of those signs... you know the one they place a little ways before a stop sign, warning you that there is indeed a stop sign up ahead so you can prepare yourself. I'd hate to have to slam on the brakes whilst traveling a few hundred thousand miles per hour!
 
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Something else I was wondering... if you were driving along at night, at the speed of light with your headlights on... would you be able to see where you were going?

terminal velocity of a car is just over 700 mph. not quite fast enough for acheiving the jump to light speed there Han Solo

P.S. I know you were joking but i couldnt resist

han_solo.jpg
 
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Something else I was wondering... if you were driving along at night, at the speed of light with your headlights on... would you be able to see where you were going?

I think yes, you will see where you were going. Its like a fighter jet shooting its guns, the speed of the guns are projected faster than at the speed its going than sitting still.
 
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I think yes, you will see where you were going. Its like a fighter jet shooting its guns, the speed of the guns are projected faster than at the speed its going than sitting still.

While I understand what you're saying, your analogy doesn't work, since nothing can exceed the speed of light. In fact nothing with mass can travel the speed of light. OK - I'm done pulling this off track. Sorry to contribute to this everyone.
 
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terminal velocity of a car is just over 700 mph. not quite fast enough for acheiving the jump to light speed there Han Solo

P.S. I know you were joking but i couldnt resist

han_solo.jpg

This may be the aerospace engineer in me, but where do you get 700 mph for the terminal velocity of a car? Unless your using a different meaning for the term, I assume that it means the free fall speed of an object once the downward force equals that of the upward force causing no acceleration.

If I did my math right, that would be about 90 mph for an average car, if its falling front side down.

Time to go back to the ADHD website
 
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This may be the aerospace engineer in me, but where do you get 700 mph for the terminal velocity of a car? Unless your using a different meaning for the term, I assume that it means the free fall speed of an object once the downward force equals that of the upward force causing no acceleration.

If I did my math right, that would be about 90 mph for an average car, if its falling front side down.

Time to go back to the ADHD website

It's the maximum speed an object under acceleration can reach minus fictional, gravitational, wind, and mechanical friction. Mostly determined by the shape of the object.
 
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I think yes, you will see where you were going. Its like a fighter jet shooting its guns, the speed of the guns are projected faster than at the speed its going than sitting still.

Are you certain of that? I remember learning that they originally developed the Blackbird as a fighter plane, but ended up removing the guns and missiles and turned it into a spy plane because it out ran all of the weaponry they had outfitted it with.
 
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1... yes.. airplanes been shown to out run thier own bullets and even shot by their own bullets!

2. for the sake of this question... if the headlights could show you what is in front of you.. even up to 1000 miles head...
WOULD IT MATTER????????????????
moving at over 186k mps.. what the F--- would you see???
 
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You are directly between two spaceships approaching you from opposite directions.
Each spaceship is approaching you at 90% the speed of light.
From either spaceship, what is the closing speed of the other spaceship?

(Answer: less than the speed of light, but much higher than 90% the speed of light.)
 
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If a plane was traveling the speed of light on a treadmill moving in the opposite direction at the speed of light....,

The plane would travel in it's direction at the speed of light. Look up the physics, the wheels on the plane have no impact on the direction it'll fly in. A plane works by moving air under the wings to create lift, unlike how a car moves forward by relying on the wheels.
 
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Fun with physics - here goes.

Light isn't a speed per se - it looks like one - (approximately) 186,282 miles/second (aka - c - the speed of light).

That looks like speed - like 80 miles/hour.

But it's really a conversion factor. Just like 2.54 cm/inches changes your notation of length - 186,000 miles/second changes your notation from the 3 x, y, and z measures of a location in space to a location in time - or more specifically - spacetime.

At speeds close to the speed of light, time changes compared to what you'd consider normal. We've all seen the hard-to-understand, but ever-popular, thing on the science channel where you hop in a spaceship and go near c in speed back and forth to some star - a few years pass for you while on Earth, your friends die off, and you come home to your grandchildren.

Because you've left the more-space-kinda-spacetime and gotten closer to the more-time-kinda-spacetime.

What about at the speed of light?

Because the speed of light is a conversion factor - at the speed of light, there is no time with respect to space.

We say that Proxima Centauri is about 4.3 light years away - light takes some 4 years to reach us from there.

For the photons that hit us from Proxima Centauri - or any star or galaxy - no time has passed at all. For us, some 4 years passed - for the photons, no time has passed.

At the speed of light, there is no distance in time - only distance in space. Time is instantaneous everywhere.

So the first reason that you can't go faster than the speed of light is because you can't go slower than the speed of light. You're going to go at that speed through spacetime, because it's a conversion factor.

This is why for all speeds below c, no matter how much or howlittle below c, the speed of light will always measure at about 186,282 miles / second. Just like 2.54 cm/inch is always true no matter how fast you go.

Why can't you travel at the speed of light?

When things move, they have momentum - move faster, more momentum - swing a hammer and you know it's true.

So - news flash - E=mc^2 is not true - it's a popular fiction and a simplification.

The real equation is E=mc^2/square_root(1 - v^2/c^2) where v is your speed - this accounts for that pesky momentum thingy while also calculating equivalent energy (E) of anything with mass (m). If you move at the speed of light, then v^2/c^2 becomes c^2/c^2 - which is one - and square_root(1-1) is square_root(0) which does not compute.

So nothing with mass can travel at the speed of light.

Photons can, because they have no mass.

But - there's the solar wind and sci-fi books say you can build a solar sail and cruise in space that way. How so if photons have no mass? Because they still have momentum. Another rule they get to break, just like they break the time-standing-still rule.

So, if your car were traveling at the speed of light - how much time would pass to see what's ahead?

No time whatsoever - you're already simultaneously there while traveling there.

Cheers!

PS - for a full discussion, see also - Amazon.com: Relativity Visualized (9780935218053): Lewis Carroll Epstein: Books
 
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So - news flash - E=mc^2 is not true - it's a popular fiction and a simplification.

The real equation is E=mc^2/square_root(1 - v^2/c^2) where v is your speed - this accounts for that pesky momentum thingy while also calculating equivalent energy (E) of anything with mass (m). If you move at the speed of light, then v^2/c^2 becomes c^2/c^2 - which is one - and square_root(1-1) is square_root(0) which does not compute.

So nothing with mass can travel at the speed of light.

What you are saying is absolutely correct, but E=mc^2 is actually true if "m" is the relativistic mass and not the commonly known mass, which is a vulgarization as you said.

Cheers! :D
 
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