P4e: What is radioactivity?

Nuclear radiation is often misunderstood and frightening. Many people will come across nuclear radiations in everyday life. This item explores the properties and uses of nuclear radiation. 

?
What is radioactivity/activity of an object measured by?
The number of nuclear decays emitted per second.
1 of 13
What happens to radioactivity overtime?
It decreases.
2 of 13
What does nuclear radiation do to materials?
Ionises it.
3 of 13
Where does radiation come from?
The nucleus of an atom.
4 of 13
How do radioactive substances decay? and what do they give out?
Naturally and nuclear radiation, in the form of alpha, beta and gamma particles.
5 of 13
What is the definition of half-life?
The number of nuclei of the radioactive isotope in a sample to halve/The count rate from a sample containing the radioactive isotope to fall to half its starting level.
6 of 13
What is ionisation?
The removal of electrons from particles/gain on electrons by particles.
7 of 13
Are alpha particles good ionisers? Why/Why not?
Yes because they have a much larger mass and greater charge than beta particles.
8 of 13
What does radioactivity come from?
The nucleus of an atom that is unstable.
9 of 13
What is an alpha particle?
A helium nucleus.
10 of 13
What is a beta particle?
A fast moving electron.
11 of 13
What happens to a nucleus when an alpha particle is emitted?
the mass number decreases by 4, nucleus has two fewer neutrons and protons, atomic number decreases by 2, new element formed.
12 of 13
What happens to a nucleus when a beta particle is emitted?
the mass number is unchanged, nucleus has one less neutron, one more proton, atomic number increases by one, new element formed.
13 of 13

Other cards in this set

Card 2

Front

What happens to radioactivity overtime?

Back

It decreases.

Card 3

Front

What does nuclear radiation do to materials?

Back

Preview of the front of card 3

Card 4

Front

Where does radiation come from?

Back

Preview of the front of card 4

Card 5

Front

How do radioactive substances decay? and what do they give out?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Radioactivity resources »