Concept explainers
Whether the leptons are heavier than protons or neutrons and explain the reason.
Answer to Problem 1CQ
The leptons are lighter than the protons and neutrons.
Explanation of Solution
The particles were grouped into three primary groups: leptons, mesons, and baryons. The leptons are the lightest particles and include electrons, positrons, and the neutrinos involved in beta decay.
Neutrons and protons occupy more volume than electron. Electron is a point particle and an elementary particle. Neutrons and the protons are baryons and they both will make some quarks, another quantum, another point particle.
Leptons are mostly lighter particles and they include the almost massless neutrinos, the electron and the muon. The heaviest of this group is the tauon and is almost twice the mass of the proton still.
Conclusion:
Therefore, leptons are the lighter particles than the protons and neutrons.
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Chapter 21 Solutions
Physics of Everyday Phenomena
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- What is the ratio of the strength of the strong nuclear force to that of the electromagnetic force? Based on this ratio, you might expect that the strong force dominates the nucleus, which is true for small nuclei. Large nuclei, however, have sizes greater than the range of the strong nuclear force. At these sizes, the electromagnetic force begins to affect nuclear stability. These facts will be used to explain nuclear fusion and fission later in this text.arrow_forwardWhy couldn’t atomic nuclei exist when the e of the Universe was less than 2 minutes?arrow_forwardThe primary decay mode for the negative pion is +v . (a) What is the energy release in MeV in this decay? (b) Using conservation of momentum, how much energy does each of the decay products receive, given the is at rest when it decays? You may assume the muon antineutrino is massless and has momentum p = E/c , just like a photon.arrow_forward
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