Radioactivity

1. Radioactivity By: Abdul, Sherif, Melina And Dominic

2. 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.

3. 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.

4. 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.

5. 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. Theyare 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.

6. 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.

7. 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.

8. 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

9. 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).

10. 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, howeverifit occurs in reproductive cells, it can cause genetic defects in later generations of children, this has been seen in our lifetime at Chernobyl.

11. Chernobyl The disaster in Chernobyl happened on the early hours of April 26th1986 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.

12. 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

13. Economic effects of the Chernobyl Disaster • Incident cost the town 6.4 billion pounds • Belarus paid on Chernobyl between 1991 to 2003, 13 billion US dollars. • Over 30 years, Belarus lost resources worth 235 billion US dollars.

14. 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.

15. Credits Dominic Abdul Sherif Melina