Nuclear Fusion Process during which two or more atomic nuclei merge and form one heavier nucleus Causes the release or absorption of large quantities of energy Fuels the sun and stars Used to make hydrogen bombs Provides a relatively inexpensive alternative energy source for electric-power generation

 Nuclear reaction that splits the nucleus of an atom into smaller, subatomic particles  Sum of masses of fragments is less than original mass  Releases large amounts of energy as electromagnetic and kinetic energy  Can occur without neutron bombardment (radioactive decay)  Can be used to create a nuclear chain reaction – exponential growth

R ADIOACTIVITY Emission of energetic particles or waves from atoms Measured in rads, where one rad represents 0.01 joule of energy absorbed per kilogram of tissue Observed in the heavy elements, like uranium, and unstable isotopes, like carbon-14 Three distinct types of radiation – alpha particles (positively charged), beta particles (negatively charged), and gamma rays (neutral) Physically impossible to predict whether or not a given atomic nucleus will decay and emit radiation at any given moment

Advantages of Nuclear Power  Almost no emissions – no pollution into atmosphere  Very Productive – small amount of nuclear power generates large amount of energy  Can be sited almost anywhere (unlike oil which is mostly imported)  New reactor types designed to be physically impossible to melt-down

Disadvantages of Nuclear Power  Expensive to build nuclear plant  Waste products are highly dangerous – melt-down would pose safety hazard to people and surroundings  Expensive to clean up spillages  Products from reactors can be stolen and turned into atomic weapons

 Travels in the form of waves or high-speed particles  Through the air  our noses or mouths (breathing)  Through rain  groundwater (lakes and reservoirs)  drinking water  Through water used to cool off nuclear plants  ocean  marine life (e.g. fish)  food

 Hair loss; dry and itchy scalp  Brain damage – seizures and immediate death  Reduction in lymphocyte presence in blood – mild radiation sickness (more susceptible to infection)  Damage to gastrointestinal tract – nausea, bloody vomiting, abdominal pain and diarrhoea  Destruction of the reproductive tract – radiation sterility; birth defects

Half-life Time taken for half of the atoms in a given mass to decay Equation for half-life: τ = o.693/ λ

 Keep a safe distance away from places that have the radioactivity symbol  Eat healthy, iodine-rich foods e.g. sea vegetables, yogurt, fish, shrimp, eggs, and strawberries  Take potassium iodide pills in recommended doses if necessary

       ear_power ear_power     ed.org/EducationResources/HighSchool/Radiography/halflife1.htm ed.org/EducationResources/HighSchool/Radiography/halflife1.htm   japan japan