Question

fundamental particles present in an atom are ...

Answer 1

Protons, electrons and neutrons

Answer 2

For School Level:

Electron, Proton and Neutron are the fundamental particles.

Actual answer:

We call those particles as fundamental particles which cannot be divide further.

For that matter, protons and neutrons are not fundamental particles, as they can further subdivided.

There is an entire branch of Physics, called Particle Physics, dedicated to understanding of the fundamental particles.

Here's the classification:

There are two types of fundamental particles:

1) Fermions
2) Bosons

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1) Fermions:

Fermions are fundamental particles which form matter.
They are named after Enrico Fermi.

Fermions are further subdivided into 2 types:

1.1 Quarks
1.2 Leptons

Both differ only very slightly. Quarks interact with Strong Nuclear Force, while Leptons don't.

But both form matter.

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1.1 Quarks:

Quarks are of six flavors (types):
• Up Quark
• Down Quark
• Charm Quark
• Strange Quark
• Top Quark
• Bottom Quark

Each of the six quarks comes in three colours : red, green, blue

(It must be noted that Quarks are much smaller than wavelength of any visible light. Red, green, and blue are just creative names given in such a way to explain another property)

Our protons and neutrons are made of quarks:

Proton = 2 up quarks + 1 down quark
Neutron = 1 up quark + 2 down quarks

There's a unique property of quarks.
They always combine in such a way that their net colour charge is white.

Eg: Red + Green + Blue = White

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1.2 Leptons

Leptons also come in six types:

• Electron
• Electron Neutrino
• Muon
• Muon Neutrino
• Tau
• Tau Neutrino


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2) Bosons:

Bosons are force-carrying particles. They carry the fundamental forces.
They are named after Prof. Satyendra Nath Bose

They are of the following types:

• Gluons (they carry strong nuclear force)

• Massive Vector Bosons : W+, W- , Z° (that's zero in superscript)
(These carry the weak nuclear force)

• Photons (They carry Electromagnetic Force)

• The Higgs Boson (a.k.a The God Particle)

The Higgs Boson is supposed to have provided mass to all the particles.


This much is enough for the basics.