Particles and anti particles

Particles and Anti-Particles

Every particle has an anti-particle. This mysterious "anti-particle" has the same rest mass and opposite charge as the "particle". For example, the antiparticle of the negatively charged electron is the positively charged electron, or the positron. 

Annihilation and Pair production

These particles and anti-particles can meet each other and annihilate one another.  in this example, a proton and an anti-proton meet each other and annihilate, producing high energy gamma rays in the form of photons. Rest mass, charge, momentum and energy are conserved.

They can also be produced from a high energy photon, this is called pair production.
  in this example, a high energy photon interacts with a nucleus to produce an electron and an anti-electron. Note energy and momentum are conserved.

Photons

Photons

Photons are separate, individual bundles of electromagnetic energy. They can be described as "packets of energy".
These "packets of energy" can provide energy to lets say an electron. Once the photon meets the electron it gives it energy to move, thus resulting in kinetic energy, allowing it to move to a higher energy level. However when the electron moves from a higher energy level to a lower energy level a photon is released. This picture demonstrates a perfect example. To put this into context the stairs are electron shells inside an atom which show electrons moving from different energy levels by releasing a photon or absorbing a photon.

We can actually work out the energy of a photon by using this formula : Energy of a photon (J)=plancks constant (J/s) * frequency (Hz)
plancks constant, being a constant, is 6.63*10^-34 J/s


-In a vacuum, all electromagnetic waves travel at the same speed, at the speed of light 3.0*10^8 m/s
-Photons are emitted when a charged particle loses energy, for example when an electron "de excites" which means it moves to a different shell of a lower energy.

Matter and Radiation

Atoms

Inside the atom

An atom consists of three main components, the positive proton, the negative electron and the neutral neutron.
The proton and neutron are packed in the centre of the atom, known as the nucleus; the electrons, on the other hand, are in fact orbiting the nucleus at different energy levels known as electron shells. These different energy levels can vary between atoms with more or less electrons. As an example, an atom of sodium has three electron shells, however the hydrogen atom has only one electron shell.
Isotopes are atoms of the same element with a different number of neutrons but the same number of protons

Charge and Mass

Atoms have a mass and charge. This table represents the charge and mass of the nucleons (proton and neutron) and the electron. 

Using charge (C) and mass (Kg) we can workout the specific charge, measured in C/Kg by using this formula : Specific charge = Charge / Mass

Now this is the interesting part, which of these sub-atomic particles has the highest specific charge? I want YOU to do the calculations and reply which you think has the biggest specific charge. 

Some cool facts about atoms

-Atoms are mostly just empty space

-We know the atom consists of a proton neutron and electron, but if we look even closer there are sub-atomic particles within the sub-atomic particles!

-Everything we know is made up of atoms, a pen can contain more than a few million atoms.