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Got a question

  1. Aug 18, 2003 #1
    I'm not the brightest bulb in the pack so please bear with me. I have a problem with the whole E=mc2 equation. The fact that time is included with the measurement is beyond me. Time is a measurement itself so how can it be considered a physical property? Time is a measurement of a cycle or distance, but since our minds are capable of remembering the past, sensing the present and predicting(not like a psychic) the future we seem to be stuck refering to it as if it where a physical thing. I guess what I'm saying is I really don't understand how the frizzy haired guy came up with it? Besides, the whole one clock showing a different time than another when in motion would seem to be physical property of the increase in mass as it approaches the speed of light not time dialation.What am I missing here?
  2. jcsd
  3. Aug 18, 2003 #2


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    To physics something that is measurable IS a physical property, I am not sure what you mean.

    this is a very common thread topic, look thorough this forum and Theoretical Physics. You will find a lot of info concering your questions.
  4. Aug 19, 2003 #3

    I guess I wasn't very clear on what I said. Time is a measurement of a cycle(life, planitary rotation, whatever)so it isn't a phsyical property. It seems to be a little difficult to get your brain around it but after alot of thought I still come back to the idea that time is just that, a idea or concept. It is used to allow people to differentiate between what they have done, are doing and what they plan to do. Do I seem to make any sense? I guess it's like my theroy that nothing is what it is untill it becomes what it is. Weird thinking hunh?!!!:smile:
  5. Aug 19, 2003 #4


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    Re: Okay.....

    Time, in Physics, is like a counter. It is one of the things that must change when an object moves from point A to point B. Einstein tied time and space together, showing that they are different manifestaions of the same thing. We call it space-time.

    Generally speaking if something changes time has passed. For any given problem we are free to specify any point in time as zero. That is, we start our time counter at our convience, generally for computational ease.
  6. Aug 19, 2003 #5
    Naw, not true- not for that specific equation. E is just the total internal energy of anything regardless of time. m is really dependant on the velocity of m-naught (the mass at zero velocity - rest mass, the mass you weight on a scale), c is constant. so if you have 1 kilogram of stuff and turn it into energy, for example, by combining it with anti-particles, you recieve 9x1016 Joules of energy (1 kg)*(3x108)2)=9x1016
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