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honestrosewater
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Is defining speed as distance/time arbitrary? Would defining speed as t/d create any irrrecoverable inconsistencies?
jcsd said:Speed is always distance over time and it really has no ther meaning, so we can't define it as time/distance.
honestrosewater said:Is defining speed as distance/time arbitrary? Would defining speed as t/d create any irrrecoverable inconsistencies?
honestrosewater said:Thanks, but "We've always done it that way" doesn't answer my question.
How does t/d have no meaning? What is the difference between traveling 1 m/s and 1 s/m? To me, conceptually, both are equally valid.
But, of course, you would have to change all the effected formulas/equations. It is making these changes that may cause problems. For instance, would you define acceleration as (delta)v/(delta)t or (delta)v/(delta)d ?
honestrosewater said:Is defining speed as distance/time arbitrary? Would defining speed as t/d create any irrrecoverable inconsistencies?
wave said:What would be your speed (according to your definition) if you're at rest (in terms of the conventional definition)?
honestrosewater said:Yes, I don't know why I didn't think of that. Your speed would be undefined.
Of course, that isn't necessarily a bad thing. After all, d/t is also undefined for t=0.
I have been wondering if time/space, inverse velocity, would have any physical meaning as well.
Is defining speed as distance/time arbitrary?
Of course, that isn't necessarily a bad thing. After all, d/t is also undefined for t=0.
honestrosewater said:Of course, that isn't necessarily a bad thing. After all, d/t is also undefined for t=0.
honestrosewater said:How does t/d have no meaning?
No, it doesn't. In the definition of speed = d/t, both t and d are independent variables. In the definition of slowness = t/d, both t and d are independent variables.properphysicist said:For t/d to be valid, that would mean that the time elapsed in a given situation would depend on the distance covered.
Many of us here not only think we know relativity, we actually know relativity. In fact, many of us here are paid by various educational institutions to teach relativity to others.A counter argument from those of you who think you actually understand relativity might go something like this: you'll read the above and say - "Ah yes, but time slows down when moving at relativistic velocities." To them I would shake my head and reply thus:
"You're right. Time does slow down significantly at relativistic velocities,
chroot said:Learn relativity before trying to teach it to others.
If you're the captain of a starship, you never notice time slowing down on your own bridge -- everything looks normal inside your starship, no matter how fast you're going with respect to things outside the starship. Time does not slow down.
On the other hand, to someone on Earth watching your radio transmissions, it would appear that your clocks are slowing down.
Oh -- you mean, people like yourself. I see.properphysicist said:I was talking to those who appear to be a bunch of kids pretending to know what they're talking about after reading some introductory text rather than studying the subject under a tutor.
You're the one that started trying to shove your misconceptions about relativity down others' throats. I simply corrected you.But I do have some understanding and although what you said about reference frames is clearly true, it is inappropriate here since we are not simply talking experiencing high velocities from some moving frame (as a starship captain).
You just repeated the exact same errant phrase. Here, I'll correct it for you:When a body moves near the speed of light, time dilates and this is a function of velocity:
Time dilation exists during the object's movement from A to B. If the object is brought back to the observer, the diffence in elapsed time on their clocks can be measured directly.However, if an object moves from A to B, and is stationary at A and B with respect to your frame, then time dilation does not exist. i.e. time dilation is a function of velocity and not of position.
Your condescending response was "Time does slow down significantly at relativistic velocities," which is bullcrap. Just admit your mistake and move on.Furthermore, I did not say time slows down. I said that's what someone else would say in response to what I said. Please take another look at my post to see what was really said.
Could've fooled me, kid.i don't pretend to know everything about physics.
Well, imagine you were the captain of a shiny new starship. You take off at 0.9c for the center of the galaxy, and close all the windows so that your passengers can sleep. Every now and then during the trip, you look at your wristwatch. Everything appears normal.UltraPi1 said:Perhaps Chroot would like to explain the why of it all. Why doesn't the captain notice any difference? Why does the person on Earth notice a difference?
If the Earth observer had a very powerful telescope, he could even take pictures of the people moving around inside the cabin of the starship, and he would think the people appeared to be moving very slowly, too.
The moving twin will have aged less because the proper time along his world-line is less than that of the stationary twin.