Mass-energy equivalence Definition and 25 Threads

Posting this as I have so far not been able to find a straightforward answer to the following question. The formula for the outer event horizon of a kerr black hole is given by the following equation: $$r_+ = \frac{GM}{c^2}\left(1+\sqrt{1-\frac{J^2c^2}{M^4G^2}}\right)$$ Where ##J## is the...

I was finding the energy required to separate tritium into it's component parts, the binding energy when it hit me that how could 1amu= 931.2 MeV and 1.66e-27 kg at the same time?

I'm an amateur physics enthusiast, and there is a question that's been in the back of my mind for some time that I haven't been able to answer on my own, and haven't gotten a satisfactory answer elsewhere. First, I want to define a couple of terms and make sure my understanding isn't breaking...

Hi, today I stumbled upon a 2016 article in Scientific American about the (then) possibility of re-defining the kilogram through Planck's constant. The article is really a very quick review of the topic. At some point the author states the following "So for years, physicists have chased an...

How well is the transition between energy and mass understood? Energy can turn into matter and matter can turn into energy but what is actually happening between the two states? Imagining that matter just simply appears and disappears under an infinitesimal amount of time feels weird to me.

I think mass as a form of potential energy and am always told that this is wrong. According to wiki: "In physics, potential energy is the energy possessed by an object because of its position relative to other objects, stresses within itself, its electric charge, or other factors." Why do this...

I am not sure exactly what E = mc^2 means. 1. Does it simply means if we were able to convert mass into energy this is the amount of energy. 2. That mass and energy are different states of the same thing. An example would be water which can either be a solid (ice), a liquid (water) or a...

Using these equations I am about to prove that photons have a rest mass of zero (mathematically) ________________________________________________________________________________________ E=hc/λ Photon Energy Equation E2=(pc+mc2)2 Mass-Energy Equivalence with Momentum Equation p=h/λ Momentum...

Homework Statement Calculate the energy equivalent of the mass of an alpha particle. alpha particle (amu) = 4.00150618 u 1 amu = 1.660566*10-27 kg 1 amu = 931.5020 MeV alpha particle (kg) = 6.64465675 * 10-27 kg Homework Equations e = mc2 The Attempt at a Solution 931.5020 MeV *...

In the Wikipedia entry on mass-energy equivalence*, there is a reference to an elementary derivation of mass-energy equivalence in an article by Rohrlich (AJP 1990), which apparently expands on the original thought experiment by Einstein (ie observer in middle of moving train, light pulses...

Homework Statement The diagram shows a proton moving with Ek of (0.178)(10-12)J towards a stationary nucleus X. The proton hits X and is absorbed. The resulting nucleus splits into two alpha particles, which move off in the directions shown with equal Ek of (1.481)(10-12)J 1. Calculate the...

Simple algebra to find the strict mass–energy equivalence formula, and I can't do it! find ((m^2)*(c^4)=(E^2)-(p^2*c^2)) from (E=m*c^2*y) (p=m*y*v) (y=1/(1-(v^2/c^2))^(1/2)) Yeh i can find the m^2c^4 parts and the E^2 obvioulsy. but then i am stuck with E^2(v^2/c^2) when instead i want...

Hi. I've seen a video by MinutePhysics that talked about the mass-energy equivalence equation, usually known as E=mc^2. It said that there is an extra part to it, and I didn't really understand what it meant. (E^2)=((mc^2)^2)+((pc)^2) seems to be the full one (p being momentum) So...

This really isn't a homework question per se, but I really don't want to post in the big boys' fora. I am learning about basic modern physics at school, as the title suggests, but I am very confused on one matter. Take the tritium nucleus as an example. If tritium nucleons are separate...

While I was looking up E=mc^{2}, I have learned such formula only applies to stationary objects and for kinetic object, the formula is this: E_{r}=\sqrt{(m_{0}c^{2})^{2}+(pc)^{2}} Where E_{r} is relativistic energy and m_{0} is rest mass In the formula, what is p and what is (pc)^{2}...

Hello All, Let m be a mass, equivalent to energy E such, that E=mc^{2}. Does it follow that c is the cosmic speed limit? ====================================== To say the above with more words: 1) m is a mass 2) in some process, it is established that through...

Hello All, is the following in principle, correct: Scenario A:------------ 1A) A box with mass M contains mass m, their weight is g(m+M) 2A) the mass m is (somehow) converted to energy E=mc^{2} 3A) at this moment, the box still has weight g(m+M) Scenario B: ---------- 1B) A box...

I've always been interested in Physics so have finally decided to do a Physics degree. I've been reading various things to help prepare myself and have just been reading about the laws of thermodynamics and mass-energy equivalence. As I'm reading through different articles about these subjects...

Pair-production is the event when a particle and anti-particle is created from a single photon. We don't see 2 or more photons participating in a single pair-production event. Further, it seems in all the events of energy-mass conversion, photons act independently. Two or more photons can...

I was reading WikiPedia's entry on this, and there was one paragraph that surprised me: E = mc2 has sometimes been used as an explanation for the origin of energy in nuclear processes, but mass–energy equivalence does not explain the origin of such energies. Instead, this relationship merely...

Homework Statement My textbook is only confusing me further and I need to understand this for a presentation in front of the class! The chapter is entitled Mass-Energy Equivalence, with sub titles Relativistic Momentum and Relativistic Energy. I don't understand relativity, I'm reading the...

So, there are tons of examples of mass being converted to energy, but can energy be converted to mass? Thanks

Einstein proposed a very simple derivation to E=mc^2 in 1940s which is well-known as Einstein’s box and a brief introduction is in http://galileo.phys.virginia.edu/classes/252/mass_and_energy.html . If this event occurs in media instead of vacuum, the light speed should be u=c/n rather than c...

I'm curious about the famous formula, e=mc^2 . Since mass can be measured in any of several unit systems, shouldn't the formula read e\propto mc^2 ? Thanks!

I was thinking just a moment ago and fragments of random knowledge and ideas gathered to make this question... If I remember my college physics class correctly, an evidence of the mass-energy equivalence is that in an atom, the sum of the rest masses of the nucleons is greater than the rest...