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Questions tagged [mass-energy]

The special-relativistic relation connecting energy with mass, $ E^2 - (m c^2)^2= (pc)^2 $. May be used to provide accounting constraints in energy and momentum, both conserved in total, even in reactions where $m$ is not.

The special-relativistic relation connecting energy with mass, $ E^2 - (m c^2)^2= (pc)^2 $. May be used to provide accounting constraints in energy and momentum, both conserved in total, even in reactions where $m$ is not.

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Meaning of Einstein's equation $E=mc^2$?

Meaning of Einstein's equation $E=mc^2$? How can a $1\,\mathrm g$ mass possess energy equal to $9\times10^{13}\,\mathrm J$? What does it actually mean?
Vinayak
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Paradox of $E=mc^2$ in different states of matter

We agree that energy is higher in liquids than solids and is higher in gases than liquids. How can we fit this into $E=mc^2$. As an example; 1 kg of ice has less energy than 1 L of water, right? But masses are the same specially in the case of water…
Ali
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Why the energy of a marshmallow is so huge?

In this comment in a blog kudzu computes the energy of a marshmallow with mass $M=25 grams$ by using $E=mc^2$: $E=Mc^2 = 2.247\times 10^{+15} Joules$ I may be wrong but this seems like a huge energy for a marshmallow. Can anybody help me put this in…
Zeynel
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How does electric potential energy affect mass?

I have three questions about weights of electrically charged balloons, the last one is the main question. Question 1: Let's say we have two seesaws, each seesaw has a positive charged balloon on the left, and a negatively charged balloon on the…
stuffu
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How can we define energy?

Can we call matter without mass as energy? just a simple defintion to the word energy; massless matter= energy? and I'm not asking about photons.
Farah Bh
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What does the speed of light have to do with mass and energy?

I've been thinking about Einstein recently, and I came back to the famous equation e=mc^2. Why does this work? It's saying the difference between mass and energy happens to be the speed of light squared? I'm sure there's a larger explanation…
Rich
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Problems Understanding Mass Energy Equivalence

So I've had a problem for a long time now understanding energy-mass equivalence, in particular I've had a lot of trouble understanding how something like interatomic potentials can be seen as mass. I've heard other people on the site say it depends…
user24082
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What form of energy is released in $E = mc^2$?

In the famous mass energy equivalence $ E = mc^2$ whenever any form of mass, lets say mass defect in nuclear reactions or any other example of mass is converted to Energy, the released energy is in what form ? Heat ? Light ? Other ?
Rijul Gupta
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Dirt energy, possible?

Doesn't $E=mc^2$ mean that mass can be converted to energy? But from what I have studied in high school nuclear physics, it seems that the only "$E=mc^2$" we can get is from binding energy between nucleons. This may sound really stupid but is it…
please delete me
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Potential energy and mass

a) Can we convert energy to mass (matter) in every day life? b) When we charge a phone battery, its mass (weight) increases according to $E = mc^2$ . Does it mean we convert energy to matter? If not, how its mass increases?
Ebi
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Calculating the speed of a proton in the LHC at 7TeV without a calculator

There are several threads on this forum regarding the LHS at CERN however I am interested in a non-calc solution. I recently stumbled upon a multiple choice question about it while studying for a physics exam and am wondering if someone has an…
Alexander Stroborg
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Where will the charge of a mass will go (having some net charge) when completely converted to energy?

All my confusion began while thinking of can charge be related to energy. Now Coulomb's law state that two body having some charges apply forces on each other which is true. And according to Newton $F=ma$ means force can be exerted on a body having…
Asif Rahman
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In $E=mc^2,$ does it not matter what constitutes the mass?

I understand $E=mc^2$ calculates the amount of energy inherent in a given mass. Mass meaning "an object's resistance to acceleration (a change in its state of motion) when a net force is applied" (1) and Energy meaning "the property that must be…
cr0
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Does this make sense from mass-energy equivalence standpoint?

Over the weekend I was (in over my head) discussing mass/energy and I proposed this thought experiment. Given two separate but equal quantities of matter - one being wood, the other being gasoline - do they both have the same total energy? I am…
FJM
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Will my mass be greater in deep space compared to when I am on Earth?

Imagine a huge hand picks me up and takes me away from Earth. Will my mass increase as I move away? I am asking this because when we try to separate a nucleus into its constituent nucleons, the total mass of the separated nucleons will be greater…
Zamil Hoque Siddique
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