1. Energy from atoms
Albert Einstein is perhaps the
most famous physicist of all time.
He first came up with the idea of
getting energy from atoms.
Scientist found that large amounts
of energy could be produced by a
process known as fission, which
involves splitting atoms of uranium.
Towards the end of the
Second World War, the USA
dropped two uranium bombs
on Japanese cities – the
effects were devastating.
2. How do we get energy from atoms?
Atoms contain huge amounts of energy, and there are
two ways in which this energy can be released.
One way is to split atomic nuclei in nucleus
a process called nuclear fission.
Another way is to join nuclei
together in a process called
nuclear fusion. electrons
The energy that holds particles together in a nucleus is much
greater than the energy that holds electrons to a nucleus.
This is the why the energy released during nuclear reactions
(involving nuclei splitting apart or joining together) is much
greater than that for chemical reactions (involving electrons).
3. Einstein and E = mc2
In 1905, Albert Einstein
made the connection
between energy and
matter.
Einstein made the
prediction that a small
amount of matter
could release a huge
amount of energy.
He expressed this in,
what is probably the
most famous equation
in physics, E = mc2.
4. Why do fuel rods have to be replaced?
Eventually, the uranium-235 in fuel rods
is used up and they have to be replaced.
The spent fuel rods contain fission
products, many of which are
radioactive. Some waste isotopes are
short lived, while others will remain
radioactive for thousands of years.
Plutonium-239 is formed when uranium-238 is bombarded
by neutrons. This highly toxic material can be used as a
nuclear fuel and to make nuclear weapons.
Other significant waste isotopes include strontium-90 and
iodine-131, which are easily absorbed by the body.
Why does nuclear waste have to carefully controlled?
5. How is nuclear waste dealt with?
Spent fuel rods are sent to a reprocessing plant to recover
any usable uranium and plutonium.
Many of the isotopes in the remaining
waste have no practical purpose and
are too dangerous to be released to
the environment.
Strict regulations are followed when
handling and storing nuclear waste.
Some waste can be stored in cement
inside reinforced steel drums.
Long-term storage of nuclear waste
is a major problem. Why is it so
difficult to find suitable sites?