Measurement of Speed by Relativity

[ConfusedSci]

Can one measure one's speed based on how much energy it takes to accelerate?

 

For instance, in Newtonian Physics, increasing speed by a certain amount (say, 1 m/s) took a certain amount of energy for a certain amount of mass. In relativity, it takes more energy the higher speed you are at.

 

One might be able to use a measurement of this increase in necessary energy to calculate a seeming "absolute speed". For example, x J per 1 m/s compared to x + y J for 1 m/s at a higher speed.

 

With this in mind, one could calculate one's speed by measuring the amount of energy needed to increase speed by a certain amount. Plugging this energy into an equation that creates a graph of speed vs necessary energy needed to increase speed should show what speed one has compared to light, but in the way of creating it absolutely, because it is being compared to a constant state of speed (and thus, rest) found in nature, c.

[Mr Skeptic]

Nope. It won't work. To the moving person it will seem like they use just as much energy to accelerate.

[ConfusedSci]

Nope. It won't work. To the moving person it will seem like they use just as much energy to accelerate.

 

But doesn't it take more energy to accelerate the closer one is to the speed of light?

[Mr Skeptic]

But doesn't it take more energy to accelerate the closer one is to the speed of light?

 

Yes but you also have more energy, and also you will disagree with a different observer on how much you accelerated. You and a different observer might also disagree on your mass, the rate that time goes by, and distance.

[J.C.MacSwell]

But doesn't it take more energy to accelerate the closer one is to the speed of light?

 

Yes, From any inertial frame,

 

So how do you choose an absolute one?