Types of Radiation.Starter: On your Post it, Answer the

following questions and stick it on the board

What do you think ‘Radiation’ is?

Name a type of radiation and put it on a scale of 1 (Minor problems) 10 ( Death) for how dangerous you think it is?

1 (Might

hurt a

Fly.)

10 (Would

certain

ly kill a

Fly.)

Lesson Objectives

(F) State and recognise the three main types of nuclear radiation.

(F/H) Describe the penetrating powers of the three types of radiation and their effects.

(H) Explain ionisation in terms of removal and gain of electrons by particles.

Types of Radiation.Name: Alpha Beta Gamma

Symbol:

What is it.

Charge.

Atomic mass

Speed

Penetration power.

Ionising power.

Alpha (α) Alpha particles are emitted from the nucleus

of large atoms. They are made up of 2 protons and 2 neutrons

(Which means it is the same as a Helium nucleus with an atomic mass of 4).

They move at relatively slow speeds compared to other animations because of their size.

What do you think happens to the nucleus after the alpha particle leaves?

Beta (β) Beta particles are also emitted from the

nucleus of atoms. They are a single electron leaving the nucleus.

They move at quite fast compared to Alpha particles

What do you think happens to the nucleus after the beta particle leaves?

Problem?

Gamma (γ) Gamma radiation is a Electromagnetic wave

released from the nucleus.

As a Electromagnetic wave they move at?

The speed of light.

What do you think happens to the nucleus after the Gamma radiation leaves?

Types of Radiation.Name: Alpha Beta Gamma

Symbol: α β γWhat is it

Charge.

Atomic mass

Speed

Helium Nucleus

(2p + 2n)

High energy

electron

High energy Electromagnet

ic Wave

2 positive.

1 Negative. None.

4. Almost nothing. No mass

Relatively Slow.

Fast. Speed of light

Thin mica Thin aluminiumstops BETA

Thick leadreduces GAMMA

Skin or paper stops ALPHA

The penetration power

Types of Radiation.Name: Alpha Beta GammaSymbol: α β γ

What is itHelium Nucleus

(2p + 2n)High energy

electron

High energy Electromagnetic

Wave

Charge. 2 positive. 1 Negative. None.

Atomic mass 4. Almost nothing. No mass

Speed Relatively Slow Quite Fast Speed of light.

Penetration power.

Ionising power.

Stopped by paper or

skin.

Stopped by a few mm of aluminium

Reduced by a few inches of Lead.

Ionisation?Ionisation occurs when electrons are

removed from an atom. A charged particles will cause more

ionisation than neutral ones. A Large particle is more likely to

collide with electrons on atoms.

So with this information, Rank the Ionisation ability of the radiation types. Highest to lowest.

Types of Radiation.Name: Alpha Beta GammaSymbol: α β γ

What is itHelium Nucleus

(2p + 2n)High energy

electron

High energy Electromagnetic

Wave

Charge. 2 positive. 1 Negative. None.

Atomic mass 4. Almost nothing. No mass

Speed Relatively Slow Quite Fast Speed of light.

Penetration power.

Ionising power.

Stopped by paper or

skin.

Stopped by a few mm of aluminium

Reduced by a few inches of Lead.

High Medium Low

Summary (re: post it.). Using the different colours of Post-it

notes.Alpha = Pink post-it.Beta = Yellow post-it.Gamma = Orange post-it.

Post one for each type on the scale of 1-10, with a reason why you placed it where you did.

Don’t give in to peer pressure.1 (Might

hurt a

Fly.)

10 (Would

certain

ly kill a

Fly.)