Radioactivity

Radioactivity

Types of radioactive emission and their behaviour

Some isotopes are unstable and split up to form smaller atoms. To do this the nucleus divides and protons, nuetrons and electrons fly out. The process is called radioactive decay, the element is said to be radioactive. 

Radioactive isotopes have unstable nuclei and they may emit either one of the hree types of radiation; alpha (α), beta (β) and gamma (γ). 

• Alpha Particles consist of two protons and two neutrons. They're positively charged and are therefore helium nuclei. They are the least penetrating of the three types of radiation, they can be stopped by a thin sheet of paper or even a few centimetres of air.

• Beta Particles consist of fast moving electrons, they are negatively charged. They are more penetrating than Alpha Particles, but less pentrating than Gamma Rays. They can travel through up to 1 metre of air but are stopped by a 5mm thick sheet of aluminium.

• Gamma rays are high energy electromagnetic waves, they have no charge and are the most penetrating of the three radiations. They can pass through several centimetres of lead or more than a metre of concrete.

The effects of electric fields on radiation

When alpha, beta and gamma radiations pass through an electric field they all react differently.

Alpha particles are deflected towards the negative charge due to the fact that they're positive, heavy and slow moving.

Beta particles are deflected towards the positive charge because they are negative, light and fast moving.

Gamma rays are undeflected due to the short wavelength of the electromagnetic radiation.

The effects of magnetic fields on radiation

Magnetic fields have a similar effect as the electric fields. However, when a charged particle goes through a magnetic field it experiences a force which is referred to as the motor effect.

Alpha particles are deflected by the magnetic field, this confirms they carry a positive charge.

Beta particles are deflected by the magnetic field, in the opposite direction to alpha particles so they must…