The building block of matter

Answer 1

According to the standard model of particles that is most commonly accepted today, there are three main catagories of particle:

Hadrons - these are heavy particles that are made up of a combination of three quarks. The most common are protons (made of 2 up quarks and a down quark), neutrons (2 downs and an up), anti-protons (2 anti-ups and an anti-down) and anti-neutrons (2 anti-downs and an anti-up).

Leptons - these are light particles that as far as anyone knows do not consist of lower building blocks. examples of these include electrons, positrons, muons, and neutrinos and their anti-counterparts.

Mesons - these particles made up of 2 quarks. There are 2 main types of meson, the pi meson and the k meson. Each meson is made of a quark and an anti quark. Pi mesons do not have strangeness, but K mesons do.

Answer 2

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