Zusammenfassung der Ressource
Energy from the Nucleus
- Nuclear Fission
- Is the splitting of an atomic nucleus
- By shooting a neutron at the
nucleus of Uranium-235 creates
Uranium-236 which is unstable
- To create daughter atoms with spare neutron
- Nuclear Fusion
- Is the process of forcing two
nucli together so they form
one larger nucleus.
- You use the 2 isotopes of
hydrogen to make a helium atom
with spare neutrons
- Nuclear Issues
- The major source of
background radiation is
radon gas, which seepes
through the ground.
- This admits alpha particals
- Other sorces are
- X-rays
- Nuclear wepon testing
- Uranium and plutonium
are chemicly removed
from used fuel rods from
nuclear reacton as they
can be used again
- Workers
should... To
reduce nuclear
radiation
- Keep as far
away as posible
from the sourse
- Shield themself with lead or concreate
- Spend as
little time as
posible
asposed to
the sorce
- The Early universe
- Big Bang 13 billion years ago
- At first the univers was a hot glowing ball of radiation
- As the univers expands, over millions of years, it's tempricher fell
- Uncharged atoms were formed
- Before Galaxies
and Stars formed,
the universe was
a dark cloud of
Hydrogen and
Helium
- Dust and Gas
were pulled
together by
gravitational
atraction to
form start
- The resulting
intensiy heat
started off nuclear
fusion reactions in
the stars so they
omited light
- A galexy is a colection of billion stars held together by there own gravity
- How the
chemical
elements
formed
- Chemical elements
are formed by fusion
processes in stars
- The process
releases large
amounts of
energy
- Elements hevier than Iorn are only formed in
the final staged of the life of a big star. This
is because the process requires the input of
energy
- All the elements get distabuted
through space by the supernova
explosion
- The presence of
the hevier
elements in the
sun and inner
planets is
evidence that
they were formes
from debris
scattered by a
supernova.
- The life History of a Star
- Gravitational forces pull clouds of dust
and gas together to form a protostar
- The core gets brighter and hotter because other elements start to fuse together
- Eventually a star runs out of hydrogen nuclei, swells, cools down and turn red
- Stars radiate energy because of hydrogen fusion in the
core. This stage can continue for billions of years untill
the star runs out of hydrogen nuclei.
- The star is stable because the inwards
force of gravity is balanced by the outer
force of radiation from the core this is
called a main sequence star
- What happens next depends on the size
- A star Similar size to our sun is a red giant
- Helium and other light elements fuse to form heavier elements
- Fusion stops and the star will contract to form a white dwarf
- Eventually no more light is emmited nad it becomes a
black dwarf
- star bigger than the Sun will swell to become a supergiant
- Eventually the star explodes in a supernova. the outher layers
are thrown into space and the core is left as a nutron star
- If this is strong enough it will form a black hole