# 100m sprint - world record

#### brum

100m sprint -- world record

Let's say you run the 100 meter sprint at the speed of light. You start exactly when the race begins.

Thus, you have the fastest possible time for the 100m sprint.

100m * (1 sec /299,792,458 m) = .000000334 seconds

If you started at the earliest possible moment, this would be the fastest possible time for the 100m sprint.

Would there be any way to beat that time? Or is that the limit for the 100m world record?

NOTE: This is all purely theoretical. I know that we cannot sprint at the speed of light. This is just for the sake of learning.

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Staff Emeritus
Gold Member
That is correct.

- Warren

#### garytse86

Yes and no. However I think there is a speed limit in which a human can reach.

#### Rockazella

Now that would be .000000334 seconds from the sprinters point of view. It would seem longer for the spectators, correct?

#### jcsd

Gold Member
No it would be 0.00000034 from the spectators point of view, from the sprinters point of view (not that he should be possibly be able to have a reference point) no time would of passed.

Wouldn't the sprinter not only need to travel at the speed of light to acheive that speed but also have infinite accelration at the start too?

I'm going to write to the IOC and ask them to take into acount relativty in future for world record times.

#### Creator

Re: 100m sprint -- world record

Originally posted by brum
.

100m * (1 sec /299,792,458 m) = .000000334 seconds

If you started at the earliest possible moment, this would be the fastest possible time for the 100m sprint.

Would there be any way to beat that time?
.
Yes, you could beat that time....IF you carried the clock with you as you sprint...your recorded time would be 0.00000000 seconds!

Creator

#### Shark

Re: 100m sprint -- world record

Originally posted by brum
Let's say you run the 100 meter sprint at the speed of light. You start exactly when the race begins.

Thus, you have the fastest possible time for the 100m sprint.

100m * (1 sec /299,792,458 m) = .000000334 seconds

If you started at the earliest possible moment, this would be the fastest possible time for the 100m sprint.

Would there be any way to beat that time? Or is that the limit for the 100m world record?

NOTE: This is all purely theoretical. I know that we cannot sprint at the speed of light. This is just for the sake of learning.

You're incorrect. If a runner runs at the speed of light. The time it takes them to complete the race is exactly:

00.000000000000000000 seconds

#### maximus

Re: Re: 100m sprint -- world record

Originally posted by Shark
You're incorrect. If a runner runs at the speed of light. The time it takes them to complete the race is exactly:

00.000000000000000000 seconds

acording to whose clock?

#### Shark

Re: Re: Re: 100m sprint -- world record

Originally posted by maximus
acording to whose clock?

Who owns the clock does not affect the time. I hope you are not in charge of anything serious?!?

#### maximus

Re: Re: Re: Re: 100m sprint -- world record

Originally posted by Shark
Who owns the clock does not affect the time. I hope you are not in charge of anything serious?!?

OMG. you have to be joking. which clock is being used is essencial. to the sprinter, no time would pass, but to stationary observer exactly .0003...(whatever they said) time would pass. you should dust of that old general and special theory of relativity books.

#### Shark

Re: Re: Re: Re: Re: 100m sprint -- world record

Originally posted by maximus
OMG. you have to be joking. which clock is being used is essencial. to the sprinter, no time would pass, but to stationary observer exactly .0003...(whatever they said) time would pass. you should dust of that old general and special theory of relativity books.

Is what a bit of a joke. Dusting off the textbook isn't needed as I guarentee you I know the material better than any textbook I've read.

So, what I meant was whose clock isn't important it's where the time is measured from.

And in this case - even if the runner measured the time, you must remember that time does not move when at the speed of light for the runner.

#### maximus

Re: Re: Re: Re: Re: Re: 100m sprint -- world record

Originally posted by Shark
So, what I meant was whose clock isn't important it's where the time is measured from.
true, but more accuratly what speed relative to the speed of light it was measured from. location isn't as important.

And in this case - even if the runner measured the time, you must remember that time does not move when at the speed of light for the runner.
that's what i said, wasn't it?

sigh...

#### Shark

Re: Re: Re: Re: Re: Re: Re: 100m sprint -- world record

Originally posted by maximus
true, but more accuratly what speed relative to the speed of light it was measured from. location isn't as important.

that's what i said, wasn't it?

Matter of fact you did say that. Why the effing hell I restated it is beyond my own idiocy for ****e sake. My post was utterly pointless.

#### garytse86

that is wrong, because to the sprinter time still passes normally relative to his time, but he would see the world freeze.

#### eNtRopY

Re: Re: Re: Re: Re: Re: Re: Re: 100m sprint -- world record

Originally posted by Shark
Matter of fact you did say that. Why the effing hell I restated it is beyond my own idiocy for ****e sake. My post was utterly pointless.
If the runner is running at the speed of light, the time observed from his reference frame is exactly zero not zero with eighteen digit accuracy... you fvcking moron.

eNtRopY

P.S. I'm only picking on you because you are a dumb piece of sh:t who uses phrases like effing hell.

#### eNtRopY

I'm going to settle this argument once and for all. Use the goddamn time dilation equation:

&Delta;t = &gamma; * &Delta;t0,

&gamma; = (1 - &beta;2)^(-1/2), and

&beta; = v / c.

So if the runner is travelling at the speed of light (v = c), the change in time he observes &Delta;t0 is equal to:

&Delta;t0 = &Delta;t / &beta;, where lim{&beta; --> infinity}.

The people watching the race from a stationary frame of reference will observe the runner to run the race in time &Delta;t.

&Delta;t = d / v, where v = c.

eNtRopY

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