# M=EC2? and a few questions.

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## M=EC2? and a few questions.

 I thought a scientific calculation can only become fact if it remains true forwards and backwards? If this is the case, then can Einstein's E=MC2 also be written as M=EC2? Or is it M=E/C2? Seems right to be able to say Mass=Energy times the speed of light. But, why does the speed of light have to be squared? Isn't that implying something faster than the speed of light? I am perfectly capable of making up my own mind. Right?
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## Re: M=EC2? and a few questions.

 that'd be m = E/c^2 (after dividing both sides by c^2). without deriving the equation, you can still check whether the units are right: basic units: mass : kilograms (kg) distance: meters (m) time: seconds (s) derived units: speed = distance/time : m/s acceleration = speed/time : m/s^2 energy = mass * acceleration * distance : kg*m^2/s^2 the last equation might not be familiar, but it's the expression for the energy of motion. if a mass is accelerated at a constant rate over a distance, multiplying all 3 values together tells you how much energy was added by the acceleration. In the same way that you can only get an acceleration by dividing distance by time squared, I hope you can see, to get an energy from a mass and a speed, you have to multiply mass*speed^2. as it happens if you use the speed of light, the result is the energy inherent in a massive object when it's at rest. since in our everyday experience speeds are typically much less than that of light, that means that most of the energy in the stuff we see is present as mass, not motion. I hope that helps a bit... clear enough?
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## Re: M=EC2? and a few questions.

 ...if a mass is accelerated at a constant rate over a distance, multiplying all 3 values together tells you how much energy was added by the acceleration. Is that equation (E=MC^2) 'THE' theory of relativity? I just don't know what it has to do with the examples used to explain the theory. Such as, two people, each at opposite ends of a train car and jumping up at the same time, while someone standing outside of the moving train sees one man jumping before the other. Also, how did they get the atom bomb from this equation? I am perfectly capable of making up my own mind. Right?
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## Re: M=EC2? and a few questions.

 Dinosaur! wrote Is that equation (E=MC^2) 'THE' theory of relativity? I just don't know what it has to do with the examples used to explain the theory. Such as, two people, each at opposite ends of a train car and jumping up at the same time, while someone standing outside of the moving train sees one man jumping before the other. no, it's just one result of the theory. the core principles are 1) the speed of light is constant for all observers 2) speeds (other than that of light) are relative - no absolute frame of reference you might think that those principles are contradictory. Einstein however showed that they're not, which was pretty cool. all that weird stuff like time dilation and length contraction happens because the above principles apply simultaneously. each observer can mark out their own coordinate system for spacetime (x,y,z,t). according to principle 2, there's no special coordinate system that everyone can use, but what relativity does do is allow you to transform between coordinate systems if you know the relative velocity of the observers involved. in mathematical terms, special relativity is essentially a coordinate transformation. the examples with trains and whatnot are intended to show the strange consequences of the theory without having to do any algebra. Apparently this is necessary because everyone hates algebra. Dinosaur! wrote Also, how did they get the atom bomb from this equation? that would be a bit oversimplified. development of the atom bomb had as much to do with experimental advances like the discovery of radioactivity and atomic structure, and the theory of quantum mechanics. in nuclear reactions less than 1% of the mass is released as energy. the same thing happens in ordinary chemical reactions, it's just that the mass loss is too small to measure. so E=mc^2 isn't really telling you anything fundamental about nuclear reactions.
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## Re: M=EC2? and a few questions.

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## Re: M=EC2? and a few questions.

 In reply to this post by Alien Observer to alien observer..... you are relatively way too smart lol have a warp speed day :)
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## Re: M=EC2? and a few questions.

 Administrator PlanetGem wrote to alien observer..... you are relatively way too smart lol have a warp speed day :) I wish Alien was back here on iwonder...     this is an old post... he hasn't been around for a longggg time....   ):     but.. he is smart though ...
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## Re: M=EC2? and a few questions.

 Administrator In reply to this post by parallel400 Bumping the post up for you mardebaran2005        ..Hope my email helped you fix the problem you had on here.
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## Re: M=EC2? and a few questions.

 In reply to this post by *StarShine* Alien Observer once posted that I almost made him cry.
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## Re: M=EC2? and a few questions.

 In reply to this post by parallel400 my brain is **warped lol
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## Re: M=EC2? and a few questions.

 In reply to this post by Alien Observer "Also, how did they get the atom bomb from this equation? " Since the equation shows how much energy is contained within a massive object(particle) it just focuses the attention to getting that energy out of that object(for obvious reasons). That energy is released by splitting an atom's nucleus. Untill the Uranium(it has unstable nucleus which results in radioactivity)  came into the picture the energy that has been taken out by splitting other atoms was the same amount that was wasted for splitting it. The problem with Uranium is that it's unstable, so once the splitting starts it becomes uncontrolled and a chain reaction starts whitch releases that tremendous amount of energy in a split second, which ofcourse due to the destructive nature of man led to the discovery of the bomb.   http://chemwiki.ucdavis.edu/@api/deki/files/16111/20.7.jpg
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## ?

 In reply to this post by Alien Observer How did E=mc^2 excatly come to frution, and become so widely accepted (besides Planx urging everyone to take Einstein seriously)? Since even the remote idea of dark matter/energy did not exist during Einstein's time, how is it that E=m (energy=mass) was accepted along with E=mc^2 (energy=mass*celeritas^2). Since according to logic and common sense it would be similar to saying something like 1=1*10^2 or 1=100.