We say "Radiation inflicts great damage to the human body."
However,do you know how radiation's abilities are related to this?
This page discusses the main characteristics of penetrating power and ionization action.

　　

Penetrating power

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Penetrating power is ability of radiation to pass through substances.
It is different between the types of radiation and energy.

Well then, let's compare alpha rays with beta rays, gamma rays and neutron rays!

・Alpha rays have two protons and two neutrons so its penetrating power is low.
It can be stopped by paper.
・Beta rays contain at least one electron so it has a stronger penetrating power than alpha rays.
Beta rays are stopped by a metallic plate or a plastic board a centimeter thick.

・Gamma rays are high energy electromagnetic waves so it has a stronger penetrating power than alpha rays and beta rays.
（examine in detail →『Types of radiation』）
　Gamma rays are stopped by iron and sheets of lead.

・Neutron rays are more difficult to step than other types of radiation because they are constituted of neutrons with no electric charge.
（examine in detail →『Types of radiation』）

　Neutron rays aren't affected by protons so they have a has very strong penetrating power.
　Neutron rays re only stopped by much water and concrete.
（examine in detail →『Types of radiation』）

In order of penetrating strength the types of radiation are, neutron rays, gamma rays, beta rays, alpha rays.
　　

Ionization action

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　Another ability that atoms and molecules have is ionization action.
Let's look at the case of the alpha rays.

・Alpha rays's ionization action
　Alpha rays are made of alpha particles with a positive charge.
（examine in detail →『Types of radiation』）

When alpha rays pass through atoms,
electrons are pulled by them so electrons are outside atoms,
namely when this atom's electrons are pulled, it changes to a positive ion.