The mass of a proton is 1.67 × 10^-27 kg. For what maximum length of time could a proton-antiproton pair spontaneously come into existence, without violating any laws of physics such as conservation of energy? A)3.5 × 10^-25 s B)1.1 × 10^-16 s C)2.2 × 10^-16 s D)7.0 × 10^-27 s

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Quizplus · Accepted Answer

The correct answer is A because the energy required to create a proton-antiproton pair is 2mc^2, where m is the mass of a proton. The uncertainty principle states that the energy of a particle can be uncertain by an amount ΔE for a time Δt, where ΔEΔt ≥ h/4π, where h is Planck's constant. Therefore, the maximum time for which a proton-antiproton pair could spontaneously come into existence is Δt = h/4πΔE = h/4π(2mc^2) = 3.5 × 10^-25 s.

The Mass of a Proton Is 1