radioactivity Flashcards
(59 cards)
what’s radioactivity?
Some atoms are unstable. They break down and release radiation to become stable.
What is a half-life
The time taken for half of the radioactive nuclei in a sample to decay.
Types of Radiation
Non-Ionising Radiation (safe in small amounts)
Example: Light, radio waves, microwaves.
Ionising Radiation (can be harmful)
Example: Alpha, Beta, and Gamma radiation from radioactive materials.
e.g of radiation
Alpha Radiation (α)
Beta Radiation (β)
Gamma Radiation (γ)
what’s alpha radiation stopped by?
alpha radiation is stopped by paper or skin
what’s Beta Radiation (β) stopped by?
Beta radiation is Stopped by aluminium.
Gamma Radiation (γ)
Gamma radiation is Stopped by thick lead or concrete.
what alpha radiation?
A helium nucleus (2 protons, 2 neutrons)
what’s beta radiation?
A fast-moving electron.
what’s gamma radiation?
A wave of energy. is a type of electromagnetic wave (like X-rays but stronger) released from unstable atoms.
types of radiation
alpha beta gamma
symbol for alpha
α
symbol for beta
β
symbol for gamma
γ
dangers of alpha radiation
Dangerous if inhaled or ingested (can cause lung cancer), but not harmful outside the body.
dangers of beta adiation
More dangerous than alpha radiation if it enters the body because it can penetrate deeper into tissues.
dangers of gamma radiation
Dangerous in large doses because it can penetrate deep into tissues and organs, but less ionising compared to alpha and beta.
speed of gamma radiation
The speed of light (fastest of all radiation types).
Penetration of gamma radiation
Very high; can go through paper, aluminium, and even thick lead or concrete.
Ionising power of gamma radiation
Weak; causes less damage compared to alpha and beta.
uses of beta radiation
medical tracers, and some types of radiation therapy.
speed of beta radiation
Faster than alpha radiation.
Ionisation power of beta radiation
Moderate; it can cause damage but not as much as alpha radiation.
Penetration of beta radiation
Medium; stopped by aluminium (around 5 mm thick).