1. ## Seeing the Light

This is the classic brain teaser that EVERYONE on the planet seems to get the wrong answer to. Yes, once you solve this, you can tell this brain teaser to anyone including a physics teacher and have complete confidence that you know the right answer - even if they do not agree with you. Loungers are intelligent and educated people. It would be interesting to note their responses.
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Hypothetically, you are in a car out in space that is traveling at the speed of light. You then decide to turn on the head lights. What do you observe?
I hope it's not a repost.

2. ## Re: Seeing the Light

<span style="background-color: #FFFF00; color: #000000; font-weight: bold"><font color=yellow>
Assuming you could travel at the speed of light (considering how massive you would be and how small)
The light should travel out at the speed of light from you</font color=yellow></span hi>
Steve

3. ## Re: Seeing the Light

At least two of us <span style="background-color: #FFFF00; color: #000000; font-weight: bold"><font color=yellow>have seen the light</font color=yellow></span hi>. I hope many more respond.

4. ## Re: Seeing the Light

Why not make the puzzle more credible by specifying that I am travelling at 99.999% of the speed of light?

StuartR

6. ## Re: Seeing the Light

Same as everyone else's. Speed of light in a vacuum is always the same for all observers, regardless of their frame of reference. Everyone always sees light travelling at the speed of light.

My suggestion makes it more credible because I have rest mass, and anything with rest mass can never reach the speed of light.

StuartR

7. ## Re: Seeing the Light

Hypothetically, you are in a car with a friend out in space that is traveling at the speed of light. Another friend is "at rest" watching you pass. As you pass your friend, You turn on the head lights and the friend in the car and the friend in space measure the speed of light. What do they each determine the speed to be?

Can you explain their observations?

Steve

8. ## Re: Seeing the Light

Q1. <span style="background-color: #FFFF00; color: #000000; font-weight: bold"><font color=yellow> Each observe the light travelling at the speed of light</font color=yellow></span hi>
Q2. <span style="background-color: #FFFF00; color: #000000; font-weight: bold"><font color=yellow>No, but I cannot explain even simple things like why buttered toast always lands buttered side down (unless it is of course tied on the back of a cat - in which case the answer is indeterminate (like Schrodinger's cat). )</font color=yellow></span hi>

9. ## Re: Seeing the Light

It lands butter side down, since it is heavier <img src=/S/grin.gif border=0 alt=grin width=15 height=15> And It is only indeterminate until the observer sees it!

Steve

10. ## Re: Seeing the Light

No, the cat and toast fall until they are about a foot off the ground and then start spinning, cats always land on their feet and toast always lands butter side down. Every one knows that!

And the stand off observer sees the cat spinning because the speed of light is a constant. The cat sees its staff standing there doing nothing (as usual) and the toast things, oh no not again (al la HHGTTG)

11. ## Re: Seeing the Light

And then, of course, the mere act of seeing it might be enough to turn it buttered side down. In fact, the bread might always land buttered side up... until somebody goes and ruins it by looking at it. <img src=/S/grin.gif border=0 alt=grin width=15 height=15> But the "heavier" argument may have some merit too - since butter is denser than bread, the centre of mass of the composite bread & butter would be closer to the buttered side, so the probability of it falling buttered side down would be higher than buttered side up.

Alan

12. ## Re: Seeing the Light

Bandido

<span style="background-color: #FFFF00; color: #000000; font-weight: bold"><font color=yellow> I reckon that if the car is travelling at the speed of light and you switch on the lights, you would see nothing!

Yes, if I was driving along the M4 at 70mph and threw out a ball at 30mph straight ahead and in the direction of travel then we can safely say the ball will (initially) be travelling at 100mph, relative to the Earth.

If we put the same theory to a car travellng at SOL and you turn on the lights. Some would say "you can't travel faster than the SOL" as effectively the light from the headlamps would be travelling at 2X SOL relative to a point in space, which is impossible so therefore must only go at the SOL which is what the car is travelling at so light would not be emitted</font color=yellow></span hi>

Jerry

13. ## Re: Seeing the Light

Tim

Cats do not always land on their feet. If you hold them upside down and as you drop them, you give them a little spin........ <img src=/S/dizzy.gif border=0 alt=dizzy width=15 height=15> . Nope I better stop before any cat lovers are on the boards

Jerry
PS No animal or human was hurt during this experiment as there was a large, soft bed under them and I was about 5 years old!!

14. ## Re: Seeing the Light

Hi Jezza. See Stuart's and Steve's answers above.

15. ## Re: Seeing the Light

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