Week 3 Flashcards
What is Alpha radiation (its description electric charge relative atomic mass, penetrating power, ionizing effect and effect of electric field)?
The release of 2 protons and 2 neutrons, this is the same as releasing a helium nucleus. Electric charge: +2. Relative atomic mass: 4. Penetrating power: stopped by paper or a few cm of air. Ionizing effect: Strongly ionizing (most dangerous). Electric field: weakly deflected, attracted to the negative plate.
What is Beta radiation (its description electric charge relative atomic mass, penetrating power, ionizing effect and effect of electric field)?
High energy electron, in beta decay, a neutron in the nucleus spontaneously decays into a proton and an electron. The proton stays in the nucleus while the electron flies out. Electric charge: -1. Relative atomic mass: 1/1860 (basically nothing). Penetrating power: Stopped by a few millimetres of aluminium. Ionizing effect: Weakly ionizing. Effect of electric field: Strongly deflected, attracted to the positive plate.
What is Gamma radiation (its description electric charge relative atomic mass, penetrating power, ionizing effect and effect of electric field)?
High energy electromagnetic radiation, it’s just energy being released, gamma rays may be emitted along side alpha and beta particle. Electric charge: 0. Relative atomic mass: 0. Penetrating power: Stopped by several cm of lead or several metre of concrete. Ionizing effect: very weakly ionizing. Effect of electric field: Not deflected in any way.
Rate gamma, beta and alpha radiation from most to least dangerous.
Alpha, beta, gamma
Rate gamma, beta and alpha from fastest travelling to slowest travelling.
Gamma, beta, alpha
Rate gamma, beta and alpha from most to least penetrating.
Gamma, beta, alpha
What is nuclear fission?(DON’T NEED)
1) Splitting a large unstable nucleus of an element (such as uranium or plutonium).
2) This is accomplished by the nucleus of the atom absorbing a neutron.
3) After this the nucleus splits into 2 new nuclei of different elements (called daughter cells) that are roughly the same size (and have some energy in their kinetic store).
4) Two or three neutrons are released from the new daughter nuclei, if these neutrons are moving slow enough to be absorbed by another nucleus, they can cause more fission to occur. This is a chain reaction.
5) However, the energy that has not been transferred to the kinetic energy store is carried away by gamma rays.
6) The energy carried away by the gamma rays, and in the kinetic energy stores of the remaining free neutrons and the other decay products can be used to heat water and turn turbines.
How is energy in a fission reaction controlled?(DON’T NEED)
The amount of energy produced by fission in a nuclear reactor is controlled by changing how quickly the chain reaction occurs. This is done by using boron control rods which are lowered and raised inside a nuclear reactor to absorb neutrons.
What is nuclear fussion?(DON’T NEED)
1) In nuclear fusion two light nuclei collide at high speed and high pressure and fuse to create a large nuclei, for example hydrogen nuclei can fuse to produce a helium nucleus.
2) The heavier nucleus produced by fusion does not have as much mass as the two separate, lighter nuclei. Some of the mass of the lighter nuclei is converted into energy, this energy is released as radiation.
3) Fusion releases a lot of energy, a lot more than fission but to accomplish fusion you need high temperatures and pressures, building a fusion nuclear reactor would be really hard and expensive.
What are the risks of using radiation?(DON’T NEED)
- Radiation can enter living cells and ionize atoms and molecules this leads to tissue damage or even cancer..
- Lower doses tend to cause minor damage without killing the cells, instead you may get mutated cells that divide uncontrollably and you have a cancer tumor.
- Higher doses tend to kill cells completely, causing radiation sickness leading to vomiting, tiredness and hair loss.
What are the uses of radiation?(DON’T NEED)
- Radioactive isotopes are injected into people or they are swallowed. Then they are tracked using external detectors.
- One example is iodine-123, which is absorbed by the thyroid gland, this can be used to check if the thyroid gland is taking in iodine as it should be.
- Isotopes that are taken into the body like this are usually GAMMA (never alpha) so that the radiation passes out of the body without causing much ionization. They should have short half life too so the radioactivity inside the patient quickly disappears.
What is another use of radiation?(DON’T NEED)
- Since high doses of radiation will kill all living cells, it can be used to treat cancers.
- Gamma rays are directed carefully and at the right dose to kill the cancer cells without damaging the surrounding cells. Radiation emitting implants can be used too (usually beta emitters) these are put next to or inside the tumor.
- However, damaging the surrounding tissue is inevitable. This makes the patient feel very ill. But if the cancer is destroyed then it is worth it.
What is another use of radiation?(DON’T NEED)
Sterilizing needles, this is usually done with using heat or fire but however some of the syringes have plastic components that will melt so radiation is used.
What is another use of radiation?(DON’T NEED)
Smoke detectors
What is the difference between induced fission and spontaneous fission?(DON’T NEED)
- Spontaneous fission happens randomly due to the activity inside the nucleus.
- Induced fission happens when the nucleus is bombarded with a neutron, induced fission is used to generate nuclear power and for weapons.
