LEC 1 Flashcards
A German Physicist
Wilhelm Conrad Roentgen
The Father of Radiography
Wilhelm Conrad Roentgen
When did Wilhelm Conrad Roentgen experimented with a cathode rays to prove that powerful rays could penetrate glass?
November 8, 1895
Wilhelm Conrad Roentgen experimented with ____ to prove that powerful rays could penetrate glass.
Cathode Rays
Wilhelm Conrad Roentgen was also experimenting with the ____ and the reason why he was using a vacuum tube.
Flow of current
What was he using during the experiment with the flow of current?
Vacuum Tube
Partially free of air
Vacuum Tube
The presence of a ____ and ____ was able to produce light at a distance and stated that something travelled from the vacuum tube to where that glow of light was seen.
High voltage power and a Vacuum Tube
A presence of a high voltage power and a
vacuum tube was able to produce ____ at a distance and stated that something travelled from the vacuum tube to where that glow of light was seen.
Light
He stated that something travelled from the vacuum tube to where that glow of light was seen. He called/considered it
a ____
Ray
Science/study of radiation as used in
medicine.
Radiology
Art and science of making radiographs by
exposure of films to x-rays.
Radiography
The making of radiographs of teeth
and adjacent structures by the exposure of film to x-rays.
Dental Radiography
A picture on a film produced by the passage of x-rays through an object.
Radiograph
Form of energy carried by waves or streams of
particles through space or substances.
Radiation
High-energy form of radiation produced with
the power to penetrate substances and record image on a photograph film.
X-Radiation
Dental radiographs are one of the important ____ for a dentist.
Diagnostic tool
A dental clinic will not be complete without a ____.
X-ray machine
It is taken to further check on what he
suspects. Without this, the dentist will not know
that there’s an underlying dental caries/carious lesion
under a filling.
Radiograph
You can only take specific tooth/ teeth or you can go as far as requesting for a radiograph where you can see a bigger area like a panoramic xray to an xray of the whole skull.
Radiography
It is needed for the diagnosis for orthodontic
cases where the dentist wants to correct malocclusions.
Dental Radiographs
All matter is composed of atoms, or tiny invisible particles.
Radiation Physics
Anything that occupies space and has mass
Matter
A Fundamental unit of matter.
Atom
A dense core of the atom, is composed
of particles known as protons and neutrons
Nucleus
A Nucleus that is dense core of the atom, is composed of particles known as ____ and ____.
Protons and Neutrons
It carry positive electrical charges.
Protons
It carry no electrical charge.
Neutrons
It is tiny, negatively charged particles
that have very little mass
Electrons
The more protons, the more unstable the atoms tend to be.
TRUE OR FALSE
True
Everything found in the periodic table can be in:
- Neutral State
- Unbalanced State
Examples under Unbalanced state:
- Excitation
- Ionization
- Radioactivity
Contains an equal number of protons and electrons.
Neutral (Stable) Atom
Total electric charge of the atom is zero.
Neutral (Stable) Atom
In Neutral Atom the total electric charge of the atom is ____.
Zero
An atom that gains or loses an electron and becomes electrically unbalanced.
Ion
The production of ions, or the process of converting an
atom into ions.
Ionization
Process by which ions are formed by gain or loss of an electron from an atom or molecule.
Ionization
Movement of an electron from a lower energy level to a
higher energy level by absorbing energy
Excitation
Energy that causes an electron to move from one orbit to next.
Excitation
The process by which certain unstable atoms or elements undergo spontaneous disintegration, or decay, to attain a more balanced nuclear state.
Radioactivity
Atomic numbers above 83 are ____
Radioactive
74
Tungsten
An element that becomes very important to understand how x-rays are produced and its interaction with matter
Tungsten 74
Unstable atom
Tungsten 74
The force that attract the electrons towards the nucleus and keeps them in their orbit.
Centripetal force
The force that allows the electrons to stay in its
orbit and move around the nucleus without being moved out.
Centrifugal force
Electrons are maintained in their orbits by the electrostatic force, or attraction, between the positive nucleus and the
negative electrons.
Binding Energy
Electrons are maintained in their orbits by the ____ or ____ between the positive nucleus and the
negative electrons.
Electrostatic force / attraction,
It is determined by the distance between
the nucleus and the orbiting electron and is different for
each shell.
Binding Energy
Are measured in
electron volts (eV) or kilo electron volts (keV).
The binding energies of orbital electrons
The binding energies of orbital electrons are measured in ____.
Electron volts (eV) or kilo Electron volts (keV).
It is the amount of force needed to keep
the electron in its orbit. At the same time, it represents the amount of energy or force needed to at least remove an electron from its orbit.
Binding Energy
To be able to move an electron out, that force should be stronger or within that value.
Binding Energy
The emission and propagation of energy through space or
a substance in the form of waves or particles.
Radiation
What are the types of radiation:
- Ionizing Radiation
- Non-ionizing Radiation
What are the Ionizing Radiation:
- Particulate Radiation
- Electromagnetic Radiation
What are the Electromagnetic Radiation:
- Wave concept
- Particle concept
Radiation that is capable of producing ions by removing or adding an electron to an atom.
Ionizing Radiation
Release of electrons from an atom
Ionizing Radiation
Breaks through matter to break molecular bonds
Ionizing Radiation
This very strong force of radiation can be explained as ____.
Particles or Electromagnetic waves
Damages plants and animal life and human cells.
Particles or Electromagnetic waves
Used to treat cancer, sterilize equipment, and identify fractures (to take radiographs and diagnosis)
Particles or Electromagnetic waves
Tiny particles of matter that possess mass and travel in straight lines and at high speeds.
Particulate Radiation
It transmit kinetic energy by means of their extremely fast-moving, small masses.
Particulate Radiation
What are the types of Particulate Radiation:
- Alpha particles/rays
- Beta particles
- Neutrons
Positively charged particles
Alpha Particles/Rays
Identical to nucleus of normal (atomic mass four) helium atom
Alpha Particles/Rays
Highest ionization power
Alpha Particles/Rays
Least penetration power (can be stopped by a piece of paper)
Alpha Particles/Rays
Cause serious damage if it gets in the body due to high ionization power
Alpha Particles/Rays
Since these have high ionization power and they are positively
charged, they have weight, they are of greater weight, but since they are of greater weight, they cannot go deeper to structures and can be easily stopped but still can cause a lot of ionization. They can also cause damage when it gets in the body.
Alpha Particles/Rays
Examples and uses of Alpha Particle/Rays:
- Smoke detectors
- Used to power heart pacemakers
Negatively charged particles
Beta Particles
Produces less ionization and penetrates deeper than alpha particle
- Penetrates skin, paper, clothes
Beta Particles
Stopped by aluminum (metal), plastic, or wood
Beta Particles
Less weight, lighter
Beta Particles
Examples of Beta Particles:
- Carbon 14 tracing
- Medical uses: Treatment of cancer, Graves’ disease, eye
problems - Medical examination procedure (Positron emission
tomography)
Presented as free neutrons
Neutron Radiation
No charge
Neutron Radiation
No ionization
Neutron Radiation
Highly penetrating and most damaging nature to cellular
structure
Neutron Radiation
Used in nuclear powerplants, atomic bombs and also used for some medical diagnostics
Neutron Radiation
Movement of energy through space as a combination of electric and magnetic fields that vibrates at right angles to each other in one direction.
Electromagnetic Radiation (EMR)
It may either be ionizing and nonionizing
Electromagnetic Radiation (EMR)
What are the characterictics of EMR as WAVES:
- Velocity
- Wavelength
- Frequency
speed of light; speed of wave
Velocity
Velocity - miles/sec
186,000
Velocity - km/sec
299,800
The distance between the crest of a wave to the next crest of another wave
Wavelength
The highest point of a wave is crest.
Wavelength
The highest point of a wave is ____.
Crest
Determines the energy and
penetrating power of the radiation
Wavelength
is measured in nanometers (nm; 1 ×
10-9 meters, or one billionth of a meter) for short waves and in meters (m) for longer waves.
Wavelength
The number of wavelengths that pass a given point in a certain amount of time
Frequency
The longer the wavelength
The lower the frequency
The shorter the wavelength
The higher the frequency
All travel at a speed of light and they would only differ in ____ and ____.
wavelength and frequency
Long wavelength and low frequency
Non-Ionizing / Soft Rays
Short wavelength and high frequency
Ionizing / Hard Rays
Have greater or stronger energy based on their frequency and wavelength than Non-
Ionizing/Soft Rays
Ionizing / Hard Rays
This characterizes electromagnetic radiation as particles (discrete bundles of energy) that travel at the speed of light in a straight path or beam carrying a specific amount of
energy
Particle Concept of Electromagnetic Radiation (EMR)
The particle concept characterizes electromagnetic radiations as discrete bundles of energy called ____
photons or quanta
Causes excitation of an atom; acts on outer shell electrons
Non-ionizing Radiation
What are the examples of Non-Ionizing Radiation
- Radio Waves
- Microwaves
- Infrared
- Sound Waves
- Visible Light (Aurora Borealis)
- UV light
A high-energy, ionizing electromagnetic radiation.
X - RADIATION
Weightless bundles of energy without an electrical charge that travels in waves or particles with a
specific frequency at the speed of light.
X-rays/ X - RADIATION
X - RADIATION Frequency:
10^-8 to 10^-12 meter; 0.1 to 0.001 nm
Radio Broadcast is measured in
Meters
Microwaves are measured in
Centimeters
Visible Light is measured in
Micrometers
Ultraviolet light is measured in
Micrometers
X-rays are measured in
Nanometers
