Final answer:
The mass of an electron is less than that of a proton and neutron due to the intrinsic properties of these particles, in particular their quark content. Electrons, being elementary particles, contain no quarks unlike protons and neutrons.
Step-by-step explanation:
The mass of an electron is negligible compared to the mass of a proton and neutron because of the intrinsic properties of these particles. First, particles can be classified as fermions or bosons based on their spin. Electrons, protons, and neutrons are all fermions but differ in their mass due to the types and quantities of quarks they contain. Protons and neutrons are composed of three quarks each, while electrons are elementary particles containing no quarks. The mass of a particle generally corresponds to the number and types of quarks, making Electrons significantly lighter.
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