How many types of elementary particles are there?
An elementary particle is a simple particle which is not a combination of other particles.For example,an electron is an elementary particle.There are 30 elementary particles out of which the following 7 elementary particles are stable out the nucleus.
List of elementary particles
- Anti neutrino
Classification of elementary particles
Elementary particles can be divided into the following four categories.
- Leptons (Neutrinos,electrons and mu-mesons).
- Mesons (Pi-mesons and K-mesons).
- Baryons (Photons,Neutrons,Lambda-hyprons,Sigma -Hyprons).
The real nature of elementary particles is still not clearly understood,and so their study is one of most active branches of modern research.
All elementary particles have antiparticles ,except the photon and neutral π-meson.A particle and its anti particle can undergo annihilation.Thus an electron and a positron can annihilate each other.
That is why positrons and anti positrons are not easily found in the part of the universe where we live.An anti hydrogen atom may be formed by an anti proton and an anti electron,just as an ordinary hydrogen is formed by a proton and an electron,and it is possible that distant stars may be composed entirely of antimatter.
If matter and antimatter come close to each other ,there would be a very dangerous explosion due to their annihilation.If there are stars composed entirely of antimatter,it is good for us to remain far away from the.