TECHNOLOGY

ERNEST RUTHERFORD A SCIENTIST WHO DISCOVERED THE NUCLEUS AND PROTON OF THE ATOM, AND HELPED IN THE SPLITTING OF THE ATOM.

1932

ENRICO FERMI A SCIENTIST WHO CREATED THE FIRST FUNCTIONING NUCLEAR REACTOR, WHILE TRYING TO CREATE ATOMIC WEAPONS FOR AMERICA

1942

NUCLEAR PHYSICS

▸ What is a radioactive atom?

▸ What is nuclear fission?

RADIOACTIVE ATOMS

▸ Some atoms are radioactive. This means that they release radiation from their nucleus.

▸ A radioactive atom is unstable. This means it is easy to break apart.

▸ Some important radioactive atoms for you to remember;

▸ Uranium-235

▸ Potassium-239

NUCLEAR FISSION

▸ Fission is another word for splitting.

▸ How does nuclear fission work?

1. A neutron is fired at the nucleus of a radioactive atom.

2. It hits the nucleus of the atom and splits the nucleus into smaller nuclei.

3. In the process, it releases more neutrons and ENERGY.

4. The neutrons released hit more radioactive atoms. This is called a chain reaction.

▸ So nuclear fission is a reaction which produces lots of heat.

Radioactive Atom + Neutron

NUCLEAR FISSION

Energy/heat

USING NUCLEAR FISSION TO CREATE ELECTRICITY

▸ What do we need to do to create electricity?

▸ Rotate a coil of wire in a magnetic field

▸ What do we use to rotate the core in any power plant?

▸ Steam

▸ So what do we need the energy from nuclear fission for?

▸ To heat the water to create steam.

BENEFITS OF NUCLEAR POWER

▸ No release of toxic gases into the atmosphere, because nuclear power does not burn anything. Unlike a thermal power plant, nuclear power plants are powered by nuclear fission, which is a type of reaction.

▸ i.e. it’s much better for the environment

▸ Efficient and powerful

▸ You don’t need much uranium for a large amount of energy

▸ Today, around 11% of the world's energy comes from nuclear power plants

▸ Reliable

▸ It is not dependent on the weather (in comparison to renewable energy like wind, solar or wave power)

▸ Cheap

▸ Low fuel cost (not much uranium needed)

DISADVANTAGES OF NUCLEAR POWER▸ High risks in an accident

▸ Chernobyl

▸ Fukushima (2011)

▸ Nuclear Waste

▸ Lasts 200,000-500,000 years.

▸ Is radioactive and must be contained.

▸ Not renewable.

▸ Uranium is finite. (Just like coal, gas)

▸ High set-up costs

▸ Hinkley Point C = £18bn (£18000000000000)

▸ Potential as terrorist target

▸ These disadvantages mean that today, still 70% of the world’s energy comes from fossil fuels

FUKUSHIMA (2011)▸ 11 March 2011 - Tohoku Earthquake

▸ Reactors in Fukushima nuclear power plant automatically shut down for safety.

▸ Tsunami hit the coast of Japan, and flooded the nuclear power plant, destroying the emergency cooling generators.

▸ One of the reactors overheated, causing three nuclear meltdowns and the release of radioactive material.

NUCLEAR POWER: HIGH RISK ACCIDENTS

NUCLEAR POWER: POTENTIAL FOR TERRORISM

THE ATOMIC BOMB: NAGASAKI & HIROSHIMA

▸ By May 1945, Nazi Germany had surrendered to the Allied powers but the Japanese were still fighting.

▸ With the discovery of nuclear power, plans were made to develop a weapon using nuclear energy.

▸ In August 1945, the US dropped two atomic bombs on Japanese cities (Nagasaki and Hiroshima) killing 129,000 people and effectively ending World War 2.

▸ This is the only time that nuclear weapons have been used in history.