[21boat]

If I traveled at the speed of light and turned on my headlights would they work to see ahead at all? Could the light speed be changed?

[Capuchin]

The speed of light is different in different mediums - it's the speed of light in a vacuum that is constant. Light moves significantly slower through glass, and you can even design materials where light slows down to a few m/s.

Your first question is one that doesn't really have an answer. It's impossible to travel at the speed of light (in a vacuum), so any answer to that question is going to be unphysical.

[21boat]

Thank you so much I have been wondering for 25 years of this quire. I love science and ended up in construction.

[Capuchin]

Please feel free to ask all you want! We love nothing better when someone is truly interested in science without having to do it for homework or whatever :)

[21boat]

Thank you for the offer. I love science and trivia of the same. I have a good one to share and try this on your doctor. What's the biggest medical break through for mankind to date and the wild part is its used daily in our homes and it involves religion. I should hold off for my answer but hear it is.

SOAP.
It stooped and keep mass disease at bay. At first the commoner thought it was for eating and it didn't take. So how to get a very large MASS to use soap. The answer was to get the heads of religious group to say in church. "cleanliness was next to godliness"
I think that's so cool!

My trade has the oldest daily used hand tool that's hardly changed since the romans.My masonry trowel

A paradox I discovered in my trade thinking a lot. Does mortar hold the brick together or keep them apart. A little goofy but fun to think
I will have some more questions later Thanks again

[harum]

Imagine that you will be able to see 100-200 feet ahead with your headlights on while driving at the speed of light. The question is, Would it really help you? With the speed of light, even 1000 feet are traveled much faster than nervous system can see the obstacles, to say nothing of your reaction time. You will not be able to break in case a deer is in your way.

[andrewc24301]

The speed of light is such a FACINATING subject. Sometimes, especially on long rides, I just sit and contemplate speed of light issues in my head.

For instance, the fact that the faster you go, apparently the slower time moves. Or so I have been told.

For instance, if I left to go to a place that was one light year away, and I traveled at the speed of light, then I would return two years later, but those who I left behind would be much older.

I wonder if there is a way of calculating how old they would be?

They say, the speed of light pretty much is the end of the line as far as measurments. Looking back on some documentaries I have watched on the subject, the speed of light limits how much of the universe we can observe from Earth. Where as, we may think we can see the edge of the universe, not true, we can only see the oldest light within our range, there could be older light that will never be seen by us. They had a way of explaining it, but it eludes me.

Not that I'm an expert on the subject, but I sure like talking to people who are.

I would really like to know what the universe is expanding into.

Where does it end?

At that end, what is on the other side?

The fact that our entire universe may just be but one drop in an ocean.

Makes my head hurt.

[harum]

You are talking about the twin paradox, a thought experiment by Einstein. There is a good article about calculations on this on Wikipedia. Yes, if you know the speed and distances, then you cancalculate exactly the age difference.

[fattybum4444]

You can travel at the speed of sound, but not at the speed of light ;)