Are protons and neutrons considered point particles?

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SUMMARY

Protons and neutrons are not considered point particles; they possess a non-zero size and are made up of quarks and gluons. Specifically, protons and neutrons have a measured radius of approximately 0.8 femtometers (fm). Their mass does not correlate with size, as there exist elementary particles with significantly greater mass than protons and neutrons. The shape of these subatomic particles is generally spherical, although this is subject to measurement uncertainties.

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magdi_gamal
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I find it confusing, I tried to google the topic but I still don't get it. What is the size and shape of subatomic particles? do they have a size or shape at all? and does the fact that protons and neutrons have larger mass than electrons mean they're bigger in size?
 
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Protons and neutrons are made out of quarks and gluons, see Wikipedia:proton for a more detailed description. Shape and size are a bit problematic to define in quantum mechanics, but independent of the chosen definition, they have a non-zero size, and the shape is spherical within the measurement uncertainties.

This has nothing to do with their mass. There are elementary particles* that have ~100 times the mass of proton and neutron.

*or at least particles where no substructure is known, and with very good arguments for them to be really elementary
 
The proton and neutron each have a radius of a little over 0.8 fm.
 

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