Question
click below
click below
Question
Normal Size Small Size show me how
Rad physics pt1
Equipment and QC pt
Question | Answer |
---|---|
Diagnostic x-rays are produced within the tube when high-speed electrons are rapidly decelerated at encounter of anode | true, pg 431 |
What kind of atoms make up the anode | tungsten, pg 431 |
What is the source of electrons in an x-ray tube? | heated cathode filament, pg 431 |
Bremsstrahlung means...? | Braking radiation, pg 431 |
Bremsstrahlung radiation is produced when a high speed electron passes through an atom and loses energy to the positively charged nucleus and is deflected from its course. | true, pg 431 |
Bremsstrahlung radiation comprises 70% to 90% of the x-ray beam. | true, pg 431 |
Characteristic radiation occurs when an electron encounters an atom and it ejects a k shell electron leaving a vacancy in the inner shell of the atom. | true, pg 431 |
What is the energy of a characteristic ray? | The difference of the energy required to eject an inner shell electron and the energy of an L shell or outer shell electron to fill its place. Pg 431 |
What makes up the electromagnetic spectrum? | Visible light (ROYGBIV), microwaves, radio waves,x-rays, and gamma rays. pg 431 |
What is frequency's unit of measure? | Hertz (Hz), pg 432 |
What is frequency? | Number of wavelength cycles per second. pg 432 |
Ionizing radiation has the potential to break apart electrically neutral atoms resulting in negative or positive ions | true, pg 433 |
What is the primary beam of the x-ray tube? | The beam coming out of the tube focal spot before it strikes anything, pg 433 |
What is the principal factor affecting beam quantity? | mAs, pg 434 |
What is attenuation? | The gradual decrease in exposure rate as radiation passes through tissues, pg 434 |
Photoelectric effect occurs when? | A low-energy photon uses all its energy to eject an inner shell electron leaving a orbital vacancy. pg 434 |
What is Compton Scatter? | A high-energy photon ejects an outer shell electron. pg 434 |
What photon interaction with matter does most occupational dose come from? | Compton Scatter, pg 434 |
Does ionization occur in the process of Coherent Scatter? | NO, pg 435. It is important to note that this is the only interaction between x-ray photons and matter in which NO IONIZATION occurs. pg 435 |
How can we see the affects of Compton scatter on an image? | Compton scatter contributes to image fog and poses a radiation hazard to personnel. pg 434 |
What is Coherent scatter? | When an x-ray photon with very low-energy interacts with an atom and "dissolves" absorbing into the atom, leaving the atom excited. pg 435 |