Nuclear Physics

Atomism

Democritus:5th century BC

Solid Sphere Model

John Dalton: 1803

Plum Pudding Model

J.J Thomson:1897

Nuclear Model

Ernest Rutherford:1911

Planetary Model

Neils Bohr:1913

Quantum Model

Edwin Schrodinger:1926

Who discovered the neutron?

James Chadwick

What is the atomic number?

Number of protons and electrons

What is the atomic mass?

The total number of neutrons and protons

What are Ions?

The name of an atom that loses or gains electrons

What are isotopes?

The name of atoms with have the same number of protons, but too many neutrons

Radiation

The particles or waves which a unstable nucleus will emit while decaying

Alpha radiation

2 neutrons, 2 protons, : high ionising power: low penetrating ability

Beta radiation

High speed electron: low ionising ability: medium penetrating ability

Gamma radiation

A high energy, electromagnetic wave: low ionising power: high penetrating ability

What is background radiation?

Radiation from items such as radon gas, rocks, and cosmic rays

What is half life?

Half life is the time it takes for the activity of a substance to half:

Alpha decay

Results in a larger nucleus and an alpha particle

Beta radiation

Results in a smaller nucleus and a proton and electron (beta)

What is the unit of activity?

Bq (Becquerel)

What is nuclear fission?

The splitting of a heavy nuclei , into two daughter nuclei, releasing energy (Mass converts into energy) neutron absorbing a neutron

What is nuclear fusion?

The opposite of nuclear fission, it is the joining of two lighter nuclei, releasing energy

Irradiation

When an object is exposed to radiation

Contamination

Unwanted presence of radioactive materials

Radiotherapy

Using ionising radiation to mutate the dna of malignant cells, or destroy harmful tissue in the body

What are the two types of radiotherapy?

External and internal

What is external radiotherapy?

Radiation being emitted from a machine outside the body

What is internal radiotherapy?

Radiation being emitted from implants or liquids inside the body

What is the purpose of medical tracers?

To track the movement of isotopes in order to make sure that organs are working correctly, or to identify tumors.

What are x-rays?

Electromagnetic waves, which help show images of the skeleton and soft tissue