Radioactivity
By: Abdul, Sherif, Melina And
Dominic
Introduction
In this presentation we will be talking about
Radioactivity and how it works we will also talk
about the incidents that happened in different
areas. We will also talk about Hans Geiger and
the Geiger counter.
What is Radioactivity?
Radioactivity is an unstable nuclei
spontaneously decomposing at a higher stability.
The decomposition process is called
radioactivity. Energy particles are released
during the process of decomposition.
Definitions
• Radioactivity: The natural release of a stream
of particles or electromagnetic rays in nuclear
decay
• Radioactive decay: Process by which an
atomic nucleus of an unstable atom losing
energy by releasing ionizing particles.
• Half-Life: The time required for half the nuclei
in a sample of a specific isotopic species to
undergo radioactive decay.
What Are Alpha And Beta Rays?
Alpha rays are fast moving helium atoms. They
have a mass amount of energy. Alpha rays are
built up of 2 protons and 2 neutrons. Alpha rays
can be stopped by a few centimeters of air.
Beta rays are fast moving electrons. They are
built up of only 1 electron. Because electrons
are weaker then helium atoms they are able to
penetrate further. Beta Rays can be stopped by
an aluminum sheet a few millimeters thick.
What Are Gamma Rays?
Gamma rays are made up of photons just like
light but far more complex energy. Gamma rays
are nearly the same as X-Rays. The only
difference between them is how they were
produced. Gamma Rays can be stopped by only
a few centimeters of lead.
Hans Geiger
Hans Geiger was born in September 30th 1882.
He later died in September 24, 1945 (aged 62)
He was a German physicist, who was known
mostly because he was the co- creator of the
Geiger counter and the Geiger Marsden
experiment which was the experiment he did to
determine the atomic nucleus.
The Geiger Counter
A Geiger counter is used to detect radiation level, it
can be used in the following areas:
• Areas prone to potential radiation leaks, such as,
Nuclear power plants.
• X-Ray labs.
• Other emergency situations where firefighters,
police officers and hazardous material teams can
test an area for radiation.
• Archaeology, anthropology and mineral collecting
jobs
What Are The Useful Uses Of
Radioactivity?
• X-Rays - Are used to see through the human
body to view the skeletal system.
• Medical Uses – Treatment of cancer
(Radiotherapy).
Why Can Radioactivity Be Dangerous?
Radioactivity is dangerous because, they can
easily penetrate deep inside the human body,
damaging some of the cells and tissues of which
the body is made from. This damage can cause
cancer to start, howeve rif it occurs in
reproductive cells, it can cause genetic defects in
later generations of children, this has been seen
in our lifetime at Chernobyl.
Chernobyl
The disaster in Chernobyl happened on the early
hours of April 26th 1986 at Pripyat, Ukraine. In
Chernobyl one of the four reactors at Chernobyl
power station exploded. This caused a huge
toxic cloud to form which spread over Europe
and America.
Social Effects of the Chernobyl Disaster
• 7,000,000 people affected in Russia, Ukraine
and Belarus
• 270,000 people affected by cancer
• 93,000 of those cancer cases were fatal
• 60,000 people dead in Russia
• 140,000 people dead in Belarus and the
Ukraine
• 4,000 children affected from thyroid cancer
Economic effects of the Chernobyl
Disaster
• Incident cost the town 6.4 billion pounds
• Belarus paid 13 billion US dollars on Chernobyl
between 1991 to 2003.
• Over 30 years, Belarus lost resources worth
235 billion US dollars.
Japans Influence
Japan’s fatal tsunami influenced the world
because one of the reactors had been damaged
during the tsunami. This caused a nuclear leak,
contaminating the water. This has shown that
there is a lot of risks when harnessing nuclear
energy.
Credits
Dominic
Abdul
Sherif
Melina