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Author | Topic: Misconceptions of E=MC^2 | |||||||||||||||||||||||||||
kongstad Member (Idle past 2870 days) Posts: 175 From: Copenhagen, Denmark Joined: |
The most simple example I can think of is this.
In the atom, there is a nucleus and electrons. The electrons can be excited, which means they can be in higher states of energy. They will however "try" to go back to lower states. To do this they must lose som energy. They do this by emitting a photon. A photon has mass (not rest mass though), so this is an example of energy being converted to mass. You see it happen all the time, since this is the basis for microwave ovens and laser, such as those in your DVD drive. You can see an animation of this here grossly simplified though:http://www.upscale.utoronto.ca/...Model/Flash/BohrModel.html What happens in the animation is that a photon is absorbed by the electron. The photon has mass, since it has energy. When it is absorbed it excites the electron, transferring all of the energy to the electron, and the photon ceases to exist. The electron later emits a new photon with mass equivalent to the energy.
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Kapyong Member (Idle past 3442 days) Posts: 344 Joined: |
Hiya,
quote: Haven't you noticed yet that you keep writing the formula wrong?e=mc2 is wrong. The correct formula is e=mc^2. And,it DOES NOT mean moving mass at the speed of light squared. It doesn't mean that. But sadly, you don't seem to get it. Iasion
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New Cat's Eye Inactive Member |
Can you give an example of energy to mass? cavediver already did in Message 80 where he linked to this page. Yes I did check them out. I see my mistake.I should have said, "can you give me a SIMPLE example that the layman such as myself can comprehend?" But back in Message 69 you said:
quote: The "proof" of that theory exists, it is just not going to be simple. This is one of those cases where you're going to have to trust the experts.
I need a simplified version which I believe you are perfectly capable of doing but don't try. I'm sorry, but I am not perfectly capable of doing a simplified version.
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Percy Member Posts: 22392 From: New Hampshire Joined: Member Rating: 5.3 |
Iasion writes: Haven't you noticed yet that you keep writing the formula wrong?e=mc2 is wrong. The correct formula is e=mc^2. In the interests of completeness, the formula can be expressed typographically in three ways that I know of:
As you noted, E = mc2 is incorrect since it says that energy equals mass times the speed of light times 2, but most people have gotten in the habit of ignoring the mistake because they know what is meant and realize that the mistake is due to what happens when you cut-n-paste "E = mc2", since the fact that the 2 is a superscript doesn't copy. I'm sure you know all this, this is just for the benefit of Heinrik. --Percy
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NosyNed Member Posts: 8996 From: Canada Joined: |
I need a simplified version which I believe you are perfectly capable of doing but don't try. I have no evidence to prove this. It is purely my observation. You have been given enormously simple versions and explanations. If you doubt that ask for the real thing from cavediver. Then you will see the difference.
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johnfolton  Suspended Member (Idle past 5592 days) Posts: 2024 Joined: |
energy = mass * speed of light squared?
It just seems like an incredible amount of energy in one atom like a mini black hole. energy/speed of light squared = mass? It sounds like this would support string theory like energy divided by speed of light squared would equal a mass almost infinititly small in comparision to the size of the atom? speed of light squared = mass / energy?speed of light * speed of light = mass / energy? speed of light = energy / mass / speed of light? c = square root of energy divided by square root of mass ? -----------------------------------------------------------------c=e/m/c solve for c ? http://www.hostsrv.com/...app1/MSP/quickmath/02/pageGenerate----------------------------------------------------------------- Now I'm not sure what I'm saying but what I think I'm questioning is if the square root of energy divided by square root of mass it seems the speed of light squared appears to cancel out? Meaning energy divided by matter going the speed of light time cancels out or that time is dependent on how lights speed is factored. Is this why its believed were seeing the past from the present in that time cancels out when energy divided by mass approaches the speed limit of light? P.S. It just seems that by moving the forumla the speed of mass can be increased if its converted to energy. However when energy/mass approaches the speed of light it cancels out. Like time for the particle of light going at light speed time stands still because mass/energy is moving at the speed of light? Edited by johnfolton, : No reason given. Edited by johnfolton, : No reason given. Edited by johnfolton, : No reason given. Edited by johnfolton, : No reason given. Edited by johnfolton, : No reason given.
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RAZD Member (Idle past 1405 days) Posts: 20714 From: the other end of the sidewalk Joined: |
or
As you noted, E = mc2 is incorrect since it says that energy equals mass times the speed of light times 2, but most people have gotten in the habit of ignoring the mistake because they know what is meant and realize that the mistake is due to what happens when you cut-n-paste "E = mc2", since the fact that the 2 is a superscript doesn't copy. One reason to use E = m•c^2 by our ability to understand RebelAAmericanOZen[Deist ... to learn ... to think ... to live ... to laugh ... to share.
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Modulous Member Posts: 7801 From: Manchester, UK Joined: |
It just seems like an incredible amount of energy in one atom like a mini black hole. It is an incredible amount of energy. And we've measured it, and confirmed that it is an incredible amount of energy. It is nothing like a mini black hole. In order for it to be a mini black hole it would have to have a much higher density than your average run of the mill day to day atom.
It sounds like this would support string theory like energy divided by speed of light squared would equal a mass almost infinititly small in comparision to the size of the atom? The mass of an atom is not anywhere 'near' infinitely small. It is very small, though.. Meaning energy divided by matter going the speed of light time cancels out or that time is dependent on how lights speed is factored. The velocity of the mass is not part of the equation (see my first post for a more accurate statement).
Is this why its believed were seeing the past from the present in that time cancels out when energy divided by mass approaches the speed limit of light? We are seeing into the past when we look at very distant objects since it takes time the light to get to us. That's all. Not really relevant to the equation at hand other than the idea that c is a constant and finite.
It just seems that by moving the forumla the speed of mass can be increased if its converted to energy. The speed of the mass isn't in there. If you do put it in there, increasing the speed of the mass increases its energy and thus its mass. Reading all this stuff into it is leading you down crazy paths of thinking. It simply says that a thing's energy and a thing's mass are proportional to one another. Increase the energy and you increase its mass. Increase the mass and you increase its energy. In a nutshell, that's all it says. When you get that idea, you can consider plugging in the masses velocity. You will find that as it approaches the speed of light the mass (and energy) approaches an infinite value and the amount of work needed to increase the velocity further also approaches infinite. Thus you cannot make a mass travel at the speed of light since it requires infinite amount of work to be done (at least in the UK, you just can't get the staff). Edited by Modulous, : No reason given.
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Coragyps Member (Idle past 735 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
It just seems like an incredible amount of energy in one atom Incredible? Yup. The bombs that destroyed Hiroshima and Nagasaki used up about a gram of matter each to do so.
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Minnemooseus Member Posts: 3941 From: Duluth, Minnesota, U.S. (West end of Lake Superior) Joined: Member Rating: 10.0 |
The bombs that destroyed Hiroshima and Nagasaki used up about a gram of matter each to do so. The Hiroshima bomb -Little Boy - Wikipedia: quote: The Nagasaki bomb used Plutonium. Wiki didn't have mass conversion information as for the Little Boy.Fat Man - Wikipedia Moose Edited by Minnemooseus, : Changed subtitle.
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bluescat48 Member (Idle past 4190 days) Posts: 2347 From: United States Joined: |
It contained 64 kg of uranium, of which 0.7 kg underwent nuclear fission, and of this mass only 0.6 g became energy. that translates to 5.4x1013 Joules (1 Joule equals 1kilogram meter2 second-2 There is no better love between 2 people than mutual respect for each other
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Trixie Member (Idle past 3706 days) Posts: 1011 From: Edinburgh Joined: |
Just for the sake of clarity, can you post the equation then underneath post it again, but with the terms replaced with moose's numbers? This might help Heinrik.
Also, given what Fat Boy did, it might be useful to tranlate the 5.4x1013 Joules into what that would do. I know we saw what it does at Hiroshima but using that may be considered cicular, so do you have a wee table that could be posted here showing varying amounts and what they can do? I think his might help to illustrate the point. For what it's worth I'm a molecular biologist so my understanding of anything to do with physics is abysmal. I always think of E=mc2 as "I have a lump of uranium in my hand. I wonder what the maximum amount of energy that could be released from it is? Hmm.....the amount of energy that could be released depends on how much uranium I have in the first place (ie mass, represented in the equation by "m"). If I plug that mass into the equation where "m" lives, I'll get my answer" I know this is simplistic in the extreme, but I wonder if this helps at all? Edited by Trixie, : Fat Boy? Fat Boy? Fat fingers more like!!!LOL
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cavediver Member (Idle past 3644 days) Posts: 4129 From: UK Joined: |
What you have to remember is that there is nothing special about nuclear reactions creating 'mass loss'. Chemical reactions do exactly the same. If we say Little Boy was 15kilotons, then a conventional explosion of 15,000 tons of TNT will also create a mass loss of around 0.6g.
In both nuclear explosions and chemical explosuions, the energy released comes from the binding energy - binding energy of the nucleus and binding energy of the atoms/molecules. This binding energy has an assocaited mass via E=mc^2, and it is the loss of this energy that gives rise to the 'mass loss'. No actual matter was harmed in the course of either explosion
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Coragyps Member (Idle past 735 days) Posts: 5553 From: Snyder, Texas, USA Joined: |
Also, given what Fat Boy did, it might be useful to tranlate the 5.4x1013 Joules into what that would do. Lessee.....it would heat 34,000,000 gallons of water from 32F to 212F.Or it would provide fifteen million kilowatt-hours of electricity to homes.
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Rahvin Member Posts: 4032 Joined: Member Rating: 9.2 |
In both nuclear explosions and chemical explosuions, the energy released comes from the binding energy - binding energy of the nucleus and binding energy of the atoms/molecules. This is different from antimatter/matter annihilation, however, where the particles are actually fully transformed into high-energy photons. Is that correct?
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