How fast does light travel in 1 ft?

In summary, the conversation is about how much time light travels in 1 foot. The person is trying to figure out how long it would take to cover 300,000,000 meters. They use a google calculator to figure it out and find that it would take 1,000,000,000 feet. The person also mentions that a real nerd would use c=1.8 terafurlongs per fortnight.
  • #1
dan001
2
0
Hello everyone,

I was wondering if anyone could help solve my problem...

...How much time in seconds (or milleseconds) would light travel in 1ft? (assuming that it was traveling in a vacuum.)

I spent 2 and a half hours yesterday trying to solve this problem, but without much luck. I remember back in school, I would know how to do this kind of stuff, but now...well, you know.

If anyone knows the answer to this problem (and if possible, a formula), I would much apreciate it.
 
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  • #2
speed = distance / time. Use google calculator. Welcome to PF.
 
  • #3
How much time to cover 300,000,000 meters (that's about 1,000,000,000 ft)? So, how much time to cover 1 ft?
 
  • #4
cesiumfrog said:
speed = distance / time. Use google calculator. Welcome to PF.


Wow, I don't believe how I could forget something so simple.

Thanks anyways for reminding me.
 
  • #5
Gokul43201 said:
How much time to cover 300,000,000 meters (that's about 1,000,000,000 ft)?

um... wait, gimme just a ... o:)
 
  • #6
robphy said:
gimme just a ... o:)
...and a teeny, tiny bit more. :tongue2:
 
  • #7
Light travels at 1 foot / atto-fortnight, everyone knows that.
 
  • #8
mgb_phys said:
Light travels at 1 foot / atto-fortnight, everyone knows that.

You are a nerd among nerds :rofl:
 
  • #9
No, a real nerd uses c = 1.8 terafurlongs per fortnight
 
  • #10
mgb_phys said:
No, a real nerd uses c = 1.8 terafurlongs per fortnight

And watch them ponys run!
 
  • #11
mgb_phys said:
No, a real nerd uses c = 1.8 terafurlongs per fortnight

Um, what's that in Planck units?
 
  • #12
That would be a good homework question, what is Planck's constant in the furlong/firkin/fortnight system.
 
  • #13
mgb_phys said:
That would be a good homework question, what is Planck's constant in the furlong/firkin/fortnight system.

Mines a trick question. In Planck units c=1, hbar=1 and G=1. Yours is harder. What's the mass unit in the firkin system? Stones, right?
 
  • #14
mgb_phys said:
That would be a good homework question, what is Planck's constant in the furlong/firkin/fortnight system.

Using dimensional analysis,
h is in Joule-seconds or kg*(m/s)^2*s = kg*m^2/s

Although http://en.wikipedia.org/wiki/FFF_System says that firkin is a mass,
according to http://en.wikipedia.org/wiki/Firkin and google, firkin is a volume: http://www.google.com/search?q=firkin+in+m^3 .
However, since it is used with water (whose density is about 1000 kg/m^3), we have an expression for the mass in kg of a firkin of water http://www.google.com/search?q=kg+in+firkin*(1000+kg/m^3)

So, since google has a problem with numerical constants in the unit conversion,
http://www.google.com/search?q=h/1000+in+(firkin)*(kg/m^3)*furlong^2/fortnight

h / 1 000 = 4.8405995 × 10-34 (firkin * (kg / (m^3)) * (furlong^2)) / fortnight


or
h = 4.8405995 × 10^(-34) (firkin of water) * (furlong^2) / fortnight


(FYI: http://www.google.com/search?q=c+in+furlongs+per+fortnight yields
the speed of light = 1.8026175 × 10^12 furlongs per fortnight)
 
Last edited:

1. How is the speed of light defined?

The speed of light is defined as the distance that light can travel in a vacuum in one second, which is approximately 299,792,458 meters per second.

2. Is the speed of light constant?

Yes, the speed of light is considered constant in a vacuum and is a fundamental constant of the universe. It does, however, change when traveling through different materials such as air, water, or glass.

3. What is the speed of light in feet per second?

The speed of light in feet per second is approximately 983,571,056 feet per second. This is calculated by converting the speed of light in meters per second to feet per second.

4. Does light travel the same speed in all directions?

Yes, light travels at the same speed in all directions. This is known as the principle of isotropy, which states that the properties of the universe are the same in all directions.

5. Can anything travel faster than the speed of light?

According to Einstein's theory of relativity, it is impossible for anything with mass to travel at or faster than the speed of light. However, some theories suggest that particles called tachyons may be able to travel faster than light, but this has not been proven.

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