Nuclear Physics Flashcards
(24 cards)
How is power and nuclear physics related
Thermal power= no. of decays x energy per decay
Nuclear waste 6marker points
- high level waste from spent fuel rods
- cool in water pond
- recycle Uranium
- vitrify waste
- surround waste in concrete and steel and bury deep underground
Coolant role and material
Transfer thermal energy between water systems. Makes heat from fission into energy. Water.
Control rods role and material
Absorbs neutrons without become unstable. Raise and Lower. Boron and cadnium.
Moderator function and material
Slow down neutron. Made of poor absorbers of neutrons, water and graphite
Enriched Uranium
Uranium 238 enriched with Uranium 235
Critical mass
Minimum mass of fuel required for there to be a steady chain reaction
Thermal neutron
A neutron that’s at thermal equilibrium with its surroundings. Low KE and speed
What’s induced fission
A stable nucleus splits into smaller nuclei due to the absorption of a low moving neutron
What’s fission?
A heavy nucleus splits into smaller more stable nuclei
What’s fusion?
When 2 light nuclei combine into a more stable heavier nucleus
What’s Binding energy?
Energy required to separate the nucleus into its constituent protons and neutrons
What’s mass deficit
Difference in mass of nucleus and the mass of individual protons and neutrons
How can you estimate the radius of a nucleus?
Close Approach Method - KE is equal to electric potential energy
Electron Scattering - accelerate Electron so de broglie is the same as size of nucleus sin=1.22lambda/diameter of nucleus
What is Uranium dating?
More Uranium 206 found. Initial U 283 has a half life of 4.5bil years
What is carbon dating
When organism dies, no longer absorbs c14. C14 compared to initial carbon (C12) to date it. C14/C12. Can date things between 500-60000 years. If less than 500, too low activity so ratio between carbon too high. Vice versa.
What are the Applications of radioactivity?
Nuclear Power
Medicine
Carbon dating
Uranium dating
Radioisotope Power System
What’s Count rate
The amount of particles a detector detects per unit time
What’s the decay constant?
Probability that a nucleus will decay per unit time
Activity
Average decay per unit time
What does it mean by random
Equal probability for all particles to decay
Unknown time for decay
Unaffected by external factors
Can only calculate proportion of decay in a given time
What’s Radioactive Decay
Spontaneous decay of an unstable nucleus to become stable, resulting in emission of alpha beta or gamma
What is the radiation safety acronym
Shielding
Half Life
Exposure time
Moniter
Attire
Distance
What is Background radiation and what kind are there
Radiation found in environment.
Radon Gas
Rocks and buildings
Medicine
Food
Cosmic Rays
