What is the energy equivalent of a proton-antiproton pair?

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The discussion revolves around calculating the energy equivalent of a proton-antiproton pair using Einstein's equation E=mc^2. The user successfully calculated the energy equivalent of a proton's mass in joules and converted it to electronvolts (eV), obtaining values of 1.5e-10 joules and 939 MeV, respectively. However, they expressed confusion regarding the calculation of the total gamma ray energy required for proton-antiproton pair production. It was clarified that gamma rays can facilitate pair production, and the user was informed that GeV (giga-electronvolt) is a larger energy unit than MeV. The conversation highlights the complexities of particle physics and the importance of understanding concepts like pair production and energy units.
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Homework Statement


The mass of a proton is 1.67 multiplied by 10-27 kg.

(a) Find the energy equivalent of the proton's mass in joules.
(b) Convert this value to eV.
(c) Find the smallest total g ray energy that could result in a proton-antiproton pair.

Homework Equations


Einstein's famous E=mc^2

The Attempt at a Solution


I figured out (a) and (b), but am absolutely clueless as to how to approach (c). What is a "g ray"? Thanks for all your help!

For (a) I got 1.5e-10
For (b) I got 939 MeV
The answer for (c) is in GeV - not really sure what this means either.
 
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A gamma ray? Seems to be the only thing making sense in that context.
 
Hmmm... Okay, thanks. But I'm unclear about what to do with that information.
What if I do E=mc^2 with m being the combined mass of the proton and the antiproton (so really just 2 times the 1.67 etc.) and get that energy, does this get me anywhere? How do I connect that with gamma rays?
 
I don't know which educational level you are so I cannot really judge what's being asked of you. If "g ray" means gamma rays, then the question is either simplistic (to the point of being wrong) or a good deal more complicated than a) and b).

Simplistic version:
Gamma rays, more precisely the photons contained in a gamma ray, at very high energies can "spontaneously" transform into a particle anti-particle pair, usually an electron anti-electron pair (they actually do not do that spontaneously but only in the presence of a reaction partner, but that is exactly the complication I am ignoring here). This process is called pair production http://en.wikipedia.org/wiki/Pair_production" . The same way, a proton anti-proton pair could be produced by a gamma ray (photon). I do think that is the process that your question asks about. I find it a bit advanced to ask for pair production if you never heard about it.

More realistic version: In reality, the reaction partner has to be taken into account. You don't want details about that.

Final remark: Did I understand you correctly that you do not know what "GeV" is? That is giga-electronvolt: 1 GeV = 1000 MeV.
 
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Wow, thanks! That was really thorough and I understand the question now. Thanks for taking your time to help me! I truly appreciate it!
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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