export_basic concepts of radiation Flashcards
Emission of energy as electromagnetic waves or as moving subatomic particles which can cause ionization?
Radiation
How radiation enters through the body?
- Inhalation
- Ingestion
- Absorption
A stream of particles or electromagnetic waves are emitted from atoms of radioactive substances as a result of?
Nuclear Decay
Sources of radiation?
- Cosmic
- Terrestrial
- Internal Radionuclides
Natural background radiation which originates from outer space?
Cosmic Background Radiation
What sends a constant stream of cosmic radiation?
Sun and Stars
Small variation in temperature of background radiation?
Anisotropies
Radioactive material found throughout nature like soil, water and vegetation?
Terrestrial Radiation.
Common Terrestrial radioactive elements?
Thorium and Uranium.
Radioactive gas that is inhaled?
Radon
Major isotopes of concern for terrestrial radiation?
Uranium, and the decay products.
Decay products of Uranium?
Thorium, Radium, Radon.
Naturally occurring radioactive gas which can accumulate in closed places?
Radon
When an unstable atom breaks down, the nucleus turns into?
Daughter Products
Locations which have higher concentrations of uranium and thorium have higher?
Dose levels.
Give the common examples of internal radionuclides in our body?
K40 C14 Pb210
Primary source of radiation from the human body?
K40
Amount of radioactive K40 in a 70kg person?
5000Bq
Unit which symbolizes the number of atoms undergoing radioactive decay every second?
Becquerels
Sources of C14
Plant based food.
Name the two groups of man exposed to radiation?
- Members of the Public
* Occupationally Exposed Individuals
Sources of man made radiation that expose the public?
- Medical Procedures
- Consumer Products
- Nuclear Fuel Cycle
- Shipment of radioactive materials
- Nuclear weapons residue.
Most significant exposure to man made radiation comes from?
Medical Procedures.
Some isotopes used in medical imaging?
I 131 Tc 99m Co 60 Ir 192 Cs 137
Radioactive substance in tobacco?
Thorium
Radioactive substance in watches?
Tritium
Radioactive substance in Smoke detectors?
Americium
Radioactive material in lantern Mantles?
Thorium
Worst nuclear accidents?
Chernobyl and Fukushima
Where was Chernobyl?
Ukraine
Some isotopes which which affect radiation workers?
U, Co 60 Cs 137 Am 241
How is radiation exposure monitored?
Dosimeters
Two basic types of radiation?
- Particulate Radiation
* Electromagnetic Radiation
A stream of atomic or subatomic particles which carry energy?
Particulate Radiation
Forms of energy subatomic particles carry?
- Kinetic Energy
* Mass in Motion
Two properties of subatomic particles?
- Energy
* Mass
Alternative name for particle radiation?
Corpuscular Radiation.
Type of ionizing radiation ejected by the nuclei of unstable atoms. It is heavy, high energy consisting of 2 protons and two neutrons?
Alpha particles.
Subatomic particle identical to helium nucleus.
Alpha particles.
Who discovered the alpha particle?
Ernest Rutherford.
When did Ernest Rutherford discover the alpha particle?
1899.
What atom was Ernest Rutherford working with when he discovered the alpha particle?
Uranium.
Velocity of alpha particles?
one twentieth the speed of light.
What is the speed of light?
3.8 x 108 m/s
Atomic number of naturally occurring alpha emitters?
82 above.
2 alpha emitters used in industrial processes?
- Radium 226
- Polonium 210
- Americium 241
Use of Radium 226?
Treat cancer.
Use of Polonium 210?
Static Eliminator.
High velocity particle with the charge of -1.
Beta Particles
Meaning of Beta?
High speed.
Mass of beta particles?
549 millionth of one amu.
Mass of beta particle compared to protons or neutrons?
1/2000
Who discovered beta particles?
Henri Becquerel
When did Henri Becquerel discover the beta particle?
1900
Beta particles are identical to?
Electrons.
Factor which affects speed of beta particles?
Energy
Used to treat thyroid disorders?
Iodine 131
Used in biology and genetics research?
Phosphorus 32
Radioactive tracer in medical and agricultural studies?
Strontium 90
Used to ensure safety of potential new drugs?
Tritium.
Used to treat cancers?
Radium 226
Used as a static eliminator?
Polonium 210
Used in some smoke detectors?
Americium 241
Used as a dating tool?
Carbon 14
How many years can carbon 14 date?
30,000 years
A particle with no charge with about the same mass as a proton?
Neutron.
Who discovered the Neutron?
James Chadwick
When was the neutron discovered?
1932
High speed nuclear particles that have exceptional ability to penetrate other materials?
Neutrons
Only particle which can make other objects radioactive?
Neutrons.
Process of neutron emission which causes other objects to become radioactive?
Neutron activation.
Type of container which can contain neutron emitters?
Thick hydrogen containing materials.
Type of radiation where neutrons are emitted?
Neutron Radiation.
Most neutron radiation occurs in?
Nuclear Reactors.
Antimatter counterpart of the electron?
Positron.
Alternative name for positron?
Antielectron
Charge and mass of positron?
+1, same as electron.
Occurs when low energy positron collides with low energy electron.
Annihilation.
Product of annihilation?
Two or more gamma ray photons.
How to produce gamma ray photons?
Annihilation.
The two who contributed to the discovery of positrons?
- Carl D. Anderson
* Paul Adrien Maurice Dirac
Pure energy with no mass and is like vibrating or pulsating waves of electrical and magnetic energy?
Electromagnetic Radiation.
Produced by vibrating electric charges, as a result have both electric and magnetic components?
Electromagnetic Radiation.
How are electromagnetic radiation produced?
Vibrating electric Charge.
Electromagnetic Radiation consists of both?
Electric and Magnetic Components
Acts like small packets of energy
Photon.
How electromagnetic radiation travels?
Wave like pattern in straight lines.
Difference between electromagnetic radiation?
Amount of energy found in photons.
Types of electromagnetic radiation?
- Radiowaves
- Microwaves
- Infrared
- Visible Light
- Ultraviolet Light
- X-rays
- Gamma Rays
Range of wavelengths or frequencies over which electromagnetic radiation extends?
Electromagnetic Spectrum.
Have the longest wavelength and carry signals for television and phones?
Radiowaves.
Length of Long microwaves?
Foot long.
Two types of Microwaves?
Longer and Shorter Microwaves
Microwaves used to heat food?
Longer Microwaves
Microwaves used in remote sensing, radar.
Shorter Microwaves.
Lies between the visible and the microwave portion of the electromagnetic spectrum?
Infrared.
Primary source of IR?
Heat or thermal radiation.
How is thermal radiation produced?
Motion of atoms and molecules.
Three categories of infrared?
- Near Infrared
- Mid Infrared
- Far Infrared
Refers to the part of the infrared spectrum closest to visible light?
Near-Infrared
Refers to the region of infrared closer to the microwave region.
Far-Infrared.
Refers to the region of infrared in-between near and far?
Mid-Infrared
How is energy of electromagnetic radiation measured?
Electron volts (eV)
As the frequency of photons increases?
Energy in each photon increases.
As frequency increases?
Wavelength decreases.
Tends to deposit energy at localized range?
Directly Ionizing Radiation
Deposits energy along the whole path?
Indirectly Ionizing Radiation
Parts of a wave?
Crest, Trough
Formula of frequency and wavelength.
v= λf
Properties of a wave?
- Frequency
- Wavelength
- Energy
Number of Oscillations per unit time?
Frequency
Usual identifier for frequency?
Cycles per Second (cps)
Frequency is represented by?
Nu ν
Unit of measurement for frequency?
Hertz
Distance of one crest to another?
Wavelength.
Shape of wave?
Sine wave.
Greek Letter representing wavelength?
λ (Lambda)
Unit of measurement for wavelength?
Angstrom (Å)
One angstrom Unit is?
10 -10 m
1 nm is equal to how many Angstroms?
10 Å
1 nm is equal to how many meters?
10-9
When ionizing photons interact with materials setting free a single electron.
Indirectly Ionizing Radiation.
All directly ionizing radiation must be moving at?
Relativistic Speeds.
A large transfer event from primary charged particle to an electron of medium, resulting in production of relatively energetic secondary electron produces?
Delta ray
Delta rays produce?
Multiple Ionization events
Radiation with enough energy so that during interaction with an atom, it removes tightly bound electrons from orbit.
Ionizing Radiation.
Only electromagnetic waves visible to human eyes.
Visible Light
Which of the visible light spectrum has the longest wavelength?
Red
Which of the visible light spectrum has the shortest wavelength?
Violet.
Plastic object which breaks white light apart?
Prism.
Shorter wavelength than visible light?
Ultraviolet.
Three regions of UV?
- Near UV
- Far UV
- Extreme UV
Closest region of UV to optical or visible light?
Near UV.
UV region closest to X-rays?
Extreme UV
Most energetic region of UV?
Extreme UV
Lies between the near and extreme UV regions?
Far UV.
Only part of UV which can ionize?
Extreme UV.
Smaller wavelength compared to UV?
X-rays
Who discovered X-rays?
Wilhelm Conrad Roentgen.
When did Roentgen discover X-rays?
November 8, 1895, Friday Late afternoon.
Smallest wavelength, with the most energy.
Gamma Rays
Generated by nuclear explosions?
Gamma rays.
Radiation that has enough energy to move atoms around causing them to vibrate, but not enough to remove electrons.
Non ionizing radiation.
Range of non ionizing radiation?
100 Hz or less.
