The destruction of two pairs of particles with the subsequent emission of energy as radiation

A neutrino that has the same mass as the neutrino but has an opposite spin to its direction of motion

Antiparticle of the proton

Members of the Hadron family of particles with 3 quarks

The proton and the electron have equal and opposite _______

Wrapping an optically less dense material around an optical fibre to ensure effective TIR

For allowed particle reactions to be predicted then charge, lepton number, baryon number and occasionally strangeness must be ________

Angles greater than this to the normal and TIR occurs within a more dense media

l = h / mv :  l is the __ ___________ wavelength

The scattering of alpha particles through thin metal foil by large angles provides evidence for a ________ and positive nucleus

Electron ____________ is evidence for the wave nature of particles

Electrons have a wave nature and e/m radiation exhibits particle nature – this is referred to as wave-particle __________

Carbon-14 has ________ neutrons

The photon is the boson responsible for this interaction

Negative component of the atom

The energy given to one electron when accelerated through a p.d. of one volt

An application of optical fibres

E = hf  - what is E?

The forces between matter can be explained by the concept of _______ particles

In the collision of an electron with an atom – this may occur if an electron is given some energy, but not enough to completely escape the atom

These diagrams can help describe the exchange of particle – especially in beta decay and electron capture

Application of TIR

Quarks have __________ charge

E = hf – what is f?

Leptons are not thought to be composed of any other particle – they are said to be _________

The boson responsible for the strong nuclear force

Experience the strong nuclear force

In the collision of an electron with an atom – this may occur if an electron is given enough energy to be removed from the atom

Atoms that have the same number of protons but different numbers of neutrons

Elements that share the same proton number but different nucleon numbers

Member of the meson family

hf = f + something … what is the “something”?

Fundamental particle family e.g. electron, muon and neutrino

Evidence that electrons exist in discrete energy levels

l = h / mv :  m is the ____________

Members of the Hadron family of particles with a quark and an antiquark

l = h / mv :  mv is the ________

Charge on an electron

Composed of 2 down quarks and 1 up quark

The ________ number indicates the number of neutrons and protons in the atom

Protons and neutrons are found in this part of the atom

The spontaneous creation of two fundamental particles (particle and antiparticle) from the conversion of energy into matter

The spontaneous emission of electrons from a metal surface when illuminated with e/m radiation above a threshold frequency

The particle model of e/m radiation involves a _________

Member of the meson family

h is the  ________  constant

Charge on a proton

Antiparticle of the electron

Only stable baryon into which all other baryons will eventually decay

The bending of light waves as they pass the boundary through different media

The ________ index, n compares the speed of two light waves in different media

Carbon-14 has a ___________ atomic mass of 14

________ scattering gives evidence for the existence of the nucleus

Carbon-14 has ________ protons

Most alpha particles are scattered by thin gold foil by only small angles – this indicates that the nucleus is ________

______ law compares the sin of the angle of incidence to the sin of the angle of refraction

A quark characteristic

The vertical axis in a Feynman diagram

Interior angles greater than a certain angle undergo __________ ___________ ___________

Protons have two ___ and one down quark

In alpha scattering experiments the source and the thin gold foil are surrounded by a _________

l = h / mv :  v is the _____________

A neutron changing into a proton involves this interaction

The minimum energy required to emit an electron when illuminated with e/m radiation

Charge on a neutron