Prelims - Basic Concepts of Radiation

Emission of energy by atoms and transition of this energy through space. It consists of a flow of atomic and subatomic particles and waves, such as those that characterized heat.

Sources of Radiation Exposure where people are constantly exposed to small amounts of; Our bodies have adapted to it.

Sources of Radiation Exposure where 99% came from medical exposures

Natural background radiation comes from the following major sources

Radiation coming from the sun and stars. Differences in elevation, atmospheric conditions, and the Earth's magnetic field can change the dose of _____ that we receive.

The Earth itself and its atmosphere.

Main contributor of Terrestrial radiation

Largest contributor to natural radiation

Sources of Exposure through inhalation

Ingestion of trace amount of radioactive minerals such as potassium-40 and carbon-14.

From radioactive fall-out as a result of atomic weapons testing during the end of the 2nd world war

releases regulated levels of radioactive material.

Nuclear gauges, smoke detectors, some glow-in-the dark exit signs, and radiation sterilization facility may expose humans.

2 types of radiation

a stream of atomic or subatomic particles that may be charged positively (alpha particles) or negatively (beta particles) or not at all (neutrons)

Particulate radiation carry energy in the form of _____ or _____

Other term for Particulate Radiation

large subatomic fragments consisting of two protons and two neutrons identical to helium nucleus

Charge of alpha particle

High velocity electrons; Emitted by nucleus during radioactive decay

Charge of Beta Particles

emitted from the nucleus of an atom during disintegration; anti-matter of electron, and it is therefore identical to the electron

Charge of Positron or Beta positive particle

energy released from an atom in the form of neutral particles called neutrons

Disturbance in space in the form of wave and carries no mass produced by a vibrating electric waves carrying both electric and magnetic fields

a stream of small "packets" of energy

electromagnetic radiation travels in a straight line at what?

the range of frequencies over which an electromagnetic radiation can be propagated.

have the longest wavelengths in the electromagnetic spectrum; carry signals for television and cellular phones

What is used in MRI

produced by fast moving electrons that are suddenly decelerated

have the smallest wavelengths and therefore the highest energy among other types of electromagnetic radiation; These waves are generated by radioactive atoms during radioactive decays and in nuclear explosions

Electromagnetic radiation under certain conditions behaves as a wave and other times as a particle

disturbances in a medium

EM waves travel in a form of

is the speed at which the wave travels

the distance between two successive crest

the number of waves that passes a particular point per given time.

Energy of the EMR is _____ to frequency

Energy of EMR is _____ to wavelength

EMR acts as a small bundle of energy, known as photon or quantum. All photons carries a specific amount of energy that is dependent upon frequency. When photon interacts with matter, their interaction is similar to a particle.

Radiation that does not carry enough energy to dislodge an electron from an atom but can cause excitation of electron.

radiation with enough energy to remove tightly bound electrons from the orbit of an atom, causing the atom to become charged or ionized.

The removal of an orbital electron from an atom.

includes all charged particles (electrons, positrons, protons, alpha particles, heavy ions) with sufficient energy to ionize atoms or molecules.

includes x-rays, gamma rays, and all uncharged particles.