Physics WJEC GCSE Unit 2.7 Types of Radiation

Double and Triple

What is a nucleus?

The centre of an Atom, contains different combinations of Protons and Neutrons.

What is a nucleon number?

number of protons + number of neutrons

on top of an element symbol

What is a proton number?

Just the number of protons, Below the element symbol

What does the amount of Protons in an atom determine?

What element it is.

What is an isotope?

elements with same number of protons, but different number of neutrons

Give an example of an isotope

Carbon 12 and Carbon 14, Carbon 14 is an isotope

What is Radioactive decay?

the decay of an unstable isotope, due to an imbalance between protons and neutrons

why does radioactive decay happen?

Isotopes releasing radiation in an attempt to become more stable, called decaying

Why is Radioactive decay Random?

Because it is impossible to guess when a nucleus will decay, but estimations can be made from probability.

Why should any tests on radiation be taken over a long period of time/several times?

to reduce the effect of random fluctuations/ anomalies

What should you remember to do when measuring radiation?

adjust for background radiation

What is background radiation?

a low level of radiation around us at all times

name 5 natural producers of background radiation

1. Radon

2. rocks

3. buildings

4. food

5. cosmic waves

Name 2 man made sources of background radiation

1. X-ray machines etc

2. Nuclear power/testing

Why does levels of background radiation change per area?

due to different rocks, building types, and the height above sea level (this affects how much radiation is emitted from cosmic waves)

what are the three types of radiation produced from decaying?

1. alpha

2. beta

3. gamma

whats the symbol for gamma?

y

whats the symbol name of alpha?

4 He 2 or 4 a 2

Whats the symbol name of beta?

0 e -1 or 0 β -1

What is Alpha made up of?

Helium Nucleus (2 protons and neutrons)

What is Beta made up of?

High energy Electrons

What is gamma made up of?

Electromagnetic waves

What is the penetrating power of Alpha? what can it be absorbed by?

Low, can be absorbed by paper

What is the penetrating power of Beta? What can it be absorbed by?

Medium, Absorbed by aluminium.

What is the penetrating power of Gamma? What can it be absorbed by?

High, cant be absorbed but reduced by thick lead

whats the danger of Alpha OUTSIDE of the body?

Low, unlikely to reach body or any cells

whats the danger of Beta OUTSIDE of the body?

Medium

whats the danger of Gamma OUTSIDE of the body?

High, can penetrate skin and affect organs

whats the danger of Alpha Inside of the body?

High, very ionising

whats the danger of Beta Inside of the body?

Medium

whats the danger of Gamma Inside of the body?

Low, less ionising