I'm not sure why you say it is wrong, then demonstrate that it is right! Perhaps you have not understood what you are reading in Jackson?popilin said:
Interestingly, the UK magazine Practical Wireless starts its latest edition wth an editorial in which the editor reports that he has just discovered that that the (magnetic) force between two current carrying wires is caused by special relativity. He was surprised at this, having been educated as an electrical engineer (presumably in the UK) but never having heard of it. He says that he asked around his contacts and none of them had heard of it either, apart from one - a physicist. That confirms what I said a few days ago: UK EEs are not taught this, so British youngsters wanting to understand electrical engineering had better do a physics degree or study overseas.
Energy = Mass x Time
Mass is speed dependent.
No, we should reconsider the definition of time and it's linearity.
Post#501, nobody rejects the equation.
Watts = Volts x Amps,
so 2V x 1A = 2 watts.
1V x 2A = 2 watts, OMG the sky is falling.
The speed of light is constant in a relative sense.
Definition of Constant: occurring continuously over a period of time.
Time varies depending on mass and speed, therefor it is constant, but not always the same.
For math to work, you need at least one unit that for practical purposes is constant. Since we don't have any real way to know how fast we are moving, he has applied "C" as the unit representing the speed of light, whatever that may be.
Is she a scientist, a physicist, an anthropologist, a ...? ...The cure to the lost soul of man?
Don't worry, think on the western movie, Albert, the sheriff, was at the saloon drinking a glass of milk; his distant relative Alfred, the musicologist, was directing the showgirls; Max, the serious, was playing the piano (A well quantized instrument); while Erwin, the womanizing, harassed showgirls and his cat became famous for surviving so many shootings. 😀
...And then came along the Monkeys, across the universe. ...Or was it the Beatles? ...The Beach Boys?
Go Argentina Go! ...World Cup. 🙂
Go Argentina Go! ...World Cup. 🙂
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I will quote your own words
DF96 said:
If being a modest TV repairman removes me credibility, warn you that once, I have derived this result by myself
This result by itself proves that you are wrong, because a magnetic field is NOT just a Lorentz-transformed electric field as you claim.
However, if you want to struggle with calculations, I will give you a guide for a proper demonstration
Let's consider an inertial reference frame K' which is moved with velocity v with respect to another inertial reference frame K.
The Lorentz transformation can be written in general form as
xμ’ =aμν xν...μ, ν = 1,2,3,4
Where the coefficients aμν are characteristic constants of the transformation, satisfying
aμν aμλ = δνλ...μ, ν, λ = 1,2,3,4
For being the fields E and B elements of the field strength tensor Fμν, we can find its transformation properties as
F’μν = aμλ aνσ Fλσ
The rest is to sweat, it is more technical than conceptual, i.e. do the math.
This is quite correct, but I think that this is the root of your confusion, let me explain
Some authors, to be original, or just for intellectual snobbism, used charge invariance and SR to derive the magnetic force on a moving charge next to a current carrying wire, and this particular case should support your statement, however it is not enough.
As for UK EEs, don't worry, it is a world wide tendency, it is called "specialization" or to know a lot about almost nothing.
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Stick in the retarded potentials and the magnetic field comes flopping out. It's a standard derivation.
Some questions for collective brain here:
How gravity works?
How magnetism works ?
Is C really constant ?
How can we try to undrstand our "universe" , before we fully undarstand our world?
Just my stupid 2 cents 🙂
How gravity works?
How magnetism works ?
Is C really constant ?
How can we try to undrstand our "universe" , before we fully undarstand our world?
Just my stupid 2 cents 🙂
Really? Because the last time I looked C was expressed in units of velocity, which is distance/time. So even if you choose to throw away the "space" part of "space-time", you would still have "Energy = Mass / Time**2". But with your formulation, are you saying that the energy equivalent of a mass increases with time?
😀
Oh, like pi?
Thank you too! 🙂
But I am hopeless, having the best football players around the world we have not a team... 🤐
When C is said to be constant this is what it means
First lets take four people, three of those people are standing in a line next to each other facing the fourth who is standing some distance away and has a ball which he then kicks toward the three at a speed of 1 mph, at the same time one of the three starts to walk toward the ball at a speed of 0.4 mph relative to his original position, another walks away from the ball at a speed of 0.4 mph relative to his original position and the third stands still
For the person standing still, the ball would have a relative speed of 1 mph
For the person walking toward the ball, the ball will have a speed of 1.4 mph relative to him (the balls speed + his speed)
For the person walking away from the ball, the ball will have a speed of 0.6 mph relative to him (the balls speed - his speed)
Makes sense 🙂
Now, lets do the same thing with light, instead of kicking a ball person number four shines a laser beam at the other three, as before at the same time one of the three starts moving toward the direction of the laser but at a higher speed, say 0.4 times the speed of light relative to his original position (just pretend he can) another moves away from the laser beam at 0.4 times the speed of light relative to his original position and the third, like before stays where he is
For the person standing still, the laser beam is moving at the speed of light relative to him
For the person moving toward the laser beam, the laser beam is also moving at the speed of light relative to him, not 1.4 times the speed of light
And for the person moving away form the laser beam, again the laser beam is moving at the speed of light relative to him, not 0.6 times the speed of light
C is constant
Stuff like this is measurable and has been measured
First lets take four people, three of those people are standing in a line next to each other facing the fourth who is standing some distance away and has a ball which he then kicks toward the three at a speed of 1 mph, at the same time one of the three starts to walk toward the ball at a speed of 0.4 mph relative to his original position, another walks away from the ball at a speed of 0.4 mph relative to his original position and the third stands still
For the person standing still, the ball would have a relative speed of 1 mph
For the person walking toward the ball, the ball will have a speed of 1.4 mph relative to him (the balls speed + his speed)
For the person walking away from the ball, the ball will have a speed of 0.6 mph relative to him (the balls speed - his speed)
Makes sense 🙂
Now, lets do the same thing with light, instead of kicking a ball person number four shines a laser beam at the other three, as before at the same time one of the three starts moving toward the direction of the laser but at a higher speed, say 0.4 times the speed of light relative to his original position (just pretend he can) another moves away from the laser beam at 0.4 times the speed of light relative to his original position and the third, like before stays where he is
For the person standing still, the laser beam is moving at the speed of light relative to him
For the person moving toward the laser beam, the laser beam is also moving at the speed of light relative to him, not 1.4 times the speed of light
And for the person moving away form the laser beam, again the laser beam is moving at the speed of light relative to him, not 0.6 times the speed of light
C is constant
Stuff like this is measurable and has been measured
Wow it's amazing after 54 pages you don't understand the simple concepts of relativity.
Do you enjoy quoting out of context?
Your analogy is flawed from the start, and has extremely little to do with what Einstein was talking about.
Time passes by differently for the people walking at .4 MPH vs 1.4 MPH.
MPH is different for those observers.
The guy walking faster at 1.4 also has gained more mass and will age slower then the .4 MPH guy.
Neither one was traveling at the speed the other one viewed.
"Stuff like this is measurable and has been measured"
Do you enjoy quoting out of context?
Your analogy is flawed from the start, and has extremely little to do with what Einstein was talking about.
Time passes by differently for the people walking at .4 MPH vs 1.4 MPH.
MPH is different for those observers.
The guy walking faster at 1.4 also has gained more mass and will age slower then the .4 MPH guy.
Neither one was traveling at the speed the other one viewed.
"Stuff like this is measurable and has been measured"
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