Flashcards
Radiographic Physics- Unit 4: The X-Ray Circuit
Flashcards do conjunto (129)
- 1The study of distribution of fixed/stationary charges or electrons at rest.Electrostatics
- 2The process of electron charges being added or subtracted from an object (usually neutral).Electrification
- 3Charge is a property of ____.Matter
- 4Electrical charges are measured in the System International (SI) unit ____.Coulomb
- 5Some materials, such as copper & gold, have a very large number of electrons free to move about, making them good ____ of electricity.Conductors
- 6Glass & plastic have very few free electrons, making them good ____.Insulators
- 7What are the 5 Laws of Electrostatics?1)Repulsion/Attraction
2)Inverse Square Law
3)Distribution
4)Concentration
5)Movement - 8Like charges repel each other, unlike charges attract each other.Repulsion/Attraction
- 9The electrostatic force between two charges is directly proportional to the product of their quantities & inversely proportional to the square of the distance between them.Inverse Square Law
- 10Electric charges will reside only on the outside surfaces of a conductor, as they are repelling each other. ***They will reside all throughout a non-conductor.***Distribution
- 11The greatest ____ of charges will be on the surface where the curvature is greatest.Concentration
- 12Only negative charges (electrons) will move along solid conductors. **Positive charge (protons) are 2000 times heavier than electrons.**Movement
- 133 Methods of Electrification in Electrostatics:1)Friction
2)Contact
3)Induction - 14Occurs when one object is rubbed against another causing one object to acquire more electrons & the other to lose electrons.Friction
- 15Occurs when two objects touch allowing electrons to transfer from one object to another.Contact
- 16Electrons transfer without any contact.Induction
- 17The study of electric charges in motion & what we most often consider as "electricity."Electrodynamics
- 18No atoms to oppose electron movement.Vacuum
- 19Promote the flow of electrons.Gases
- 20Creates a medium for electrons to migrate from one pole to another.Ionic Solutions
- 21Any metal that allows current flow is a conductor.Metallic Conductors
- 22Pathway that permits electron movement from one point, through a wire, & then back to that point.Electric Circuit
- 23_____ creates a separation of charges & the exposure factors the radiographer selects on the control panel to determine the # of electrons that will flow & the magnitude of their attraction to the positive side.X-ray tube
- 24The ability to do work due to a separation of charges.Electric Potential
- 25What is the unit of measure for electric potential?Volt
- 26An expression of the flow of electrons in a conductor.Current
- 27Unit of measure for a current.Ampere
- 28The property of an element in a circuit that resists or impedes the flow of electricity.Resistance
- 29What's the unit of measure for resistance?Ohm
- 30____ is defined as the potential difference that will maintain a current of 1 ampere in a circuit with a resistance of 1 ohm.Volt
- 31The ___ is defined as 1 coulomb flowing by a given point in 1 second.Ampere
- 32Electrons always move from the point of ____ concentrations to lowest.Highest
- 33-Flows only in one direction -Example: BatteriesDirect Current (DC)
- 34-Changes direction in cycles as the electric potential of the source changes. -Example: The electricity in homes in the United States.Alternating Current (AC)
- 35Both ___ & ___ are used in basic x-ray production.Alternating Current (AC) & Direct Current (DC)
- 36Defined as the quantity, or number, or electrons flowing per second.Current
- 37Defined as the force with which the electrons travel through the circuit.Potential Difference
- 38Defined as the amount of opposition to the current in the circuit.Resistance
- 39The mathematical relationship between current, potential difference, & resistance.Ohm's Law
- 40Materials with an abundance of free electrons that allow a relatively free flow of electricity. (Gold, Copper)Conductors
- 41Materials made up of atoms with tightly bound electrons that do not conduct electricity well even when attracted by a potential difference. (Glass/Rubber/Plastic)Insulators
- 42Materials that will conduct electricity but not as well as conductors & that will insulate but not as well as insulators. (Silicone)Semiconductors
- 43The ____ (Longer/Shorter) the conductor, the more resistance.Longer/More
- 44___ ___ states that the potential difference (voltage) across the total circuit or any part of that circuit is equal to the current (amperes) multiplied by the resistance.Ohm's Law
- 45The (larger/smaller) ____ the diameter, the less resistance.Larger
- 46A closed (complete) pathway for electricity is required for electricity to flow.Closed Circuit
- 47An open (Broken) pathway, such as occurs when a switch is turned off.Open Circuit
- 48Circuit elements are wired along a single conductor.Series Circuit
- 49Circuit elements "bridge" or branch across a conductor.Parallel Circuit
- 50Produces electrons through a chemical reaction, stores an electric charge long term, & provides an electric potential.Battery
- 51Temporarily stores an electric charge.Capacitor
- 52A "one-way valve" device, allows electrons to flow in one direction.Diode
- 53The ____ in Ohm's is equal to the sum of each separate resistor.Total Resistance
- 54The ____ equals the sum of each separate voltage for resistor.Total Voltage
- 55____ across each resistor equals the current times the individual resistor.Voltage
- 56In a series circuit, the ___ stays the same..Current
- 57In a parallel circuit, the ___ stays the same.Voltage
- 58The process of connecting an electrical device to the earth via a conductor.Grounding
- 59Ability of a material to attract iron, cobalt, nickel.Magnetism
- 60The nature of magnetic materials is that the orbital electrons of their atoms spin in predominately ____ direction.One
- 61A magnetic field consists of lines of force in space.Flux
- 62Inside the magnetic, the flux goes from ____ to ____ direction when there is a Direct Current.South to North
- 63Outside the magnet, the flux goes from ____ to ____ direction when there is a direct current.North to South
- 64The 3 Laws of Magnetism1) Every magnet has a north/South Pole.
2)Like poles repel each other & opposite poles attract each other.
3)The force & attraction or repulsion varies directly with the strength of the poles & inversely with the square of the distance between them. - 65The 3 Types of Magnets:1)Natural
2)Artificial
3)Electromagnets - 66The strength of the magnetic field is measured in the SI unit ___.Tesla (T)
- 67Examples of nonmagnetic materials that are not attracted to the magnetic field?Glass
Wood
Plastic - 68Examples of diamagnetic materials that are weakly repelled by magnetic fields.Water
Mercury
Gold - 69Examples of Paramagnetic materials that are weakly attracted to magnetic field.Platinum
Gadolinium
Aluminum - 70Examples of Ferrimagnetic materials that are strongly attracted magnetic materials.Iron
Cobalt
Nickel - 71Magnetic materials that are: -High Permeability -Magnetic Materials -Iron, Nickel, Cobolt -Highly susceptible to induction.Ferromagnetic Materials
- 72-Low Permeability -Platinum & Aluminum -Weak attraction to magnetic fieldsParamagnetic Materials
- 73-Weakly repelled by magnetic fields -Beryllium, Bismuth, Lead, & WaterDiamagnetic Materials
- 74-Not attracted by a magnet -CANNOT be magnetized -Wood, plastic, glass -Most materials on non-magnetic.Non-Magnetic Materials
- 75Electricity & Magnetism are two parts of the same basic force. -Any flow of electrons, whether in space or in a conductor, will be surrounded by a magnetic field. -A moving field can create an electric current.Electromagnetism
- 76Devices that convert some form of mechanical energy into electrical energy.Electric Generators
- 77Moving conductor through a magnetic field induces an electric current in that conductor.Electromagnetic Induction
- 78Process by which a magnetic field induces a current in the same wire & created a resistance within the circuit.Self-Induction
- 79Coverts electrical to mechanical energy through electromagnetic induction.Motors
- 80What devices controls electrical voltage & current?-Transformers
-Autotransformers
-Capacitors - 81A step-up transformer (Increases/Decreases) ____. voltage.Increases
- 82A step-down transformer (Increases/Decreases) ____ voltage.Decreases
- 83Types of transformers:-Air Core
-Open Core
-Closed Core
-Shell Type - 84The x-ray circuit may be divided into 3 sections:1) Primary Circuit
2) Secondary Circuit
3) Filament Circuit - 85The main power switch is simply an on-off switch for the unit & is connected to the power supply of the facility.Primary Circuit
- 86Device usually wired to the autotransformer that automatically adjusts the power supplied to the x-ray machine to 220 volts.Line Compensator
- 87Protect against short circuits & electric shock.Circuit Breakers
- 88An adjustable transformer controlled by the kilovolt peak (kVp) elector on the control panel.Autotransformer
- 89Primary & secondary coils are filled with an iron core to increase the strength of the magnetic field.Open Core
- 90Two coils of wire in proximity to facilitate induction.Air Core
- 91Closing the core by placing a top & bottom on the iron cores.Closed Core
- 92Consists of the secondary side of the step-up transformer, the mA meter, a rectifier bank, & the X-ray tube.Secondary Circuit
- 93Consists of rheostat, a step-down transformer, & the filaments.Filament Circuit
- 94Rectifier changes the ___ to ___.AC & DC
- 95This increases the heating capacity of the X-ray tube thus permitting larger exposures.Rectifier/Diode
- 96Back-up mAs should at least be set at ____%.150%
- 97When using the AEC, you should only be adjusting the ___ on the control panel.kVp
- 98____ always flow from cathode to anode.Electrons
- 99The diodes permit the flow of the electrons from cathode to anode through the X-ray tube. (HALFWAVE RECTIFICATION)Positive Half
- 100The diodes suppress the negative half of the AC cycle by acting as a non-conductor or an open switch & this prevents the electrons from flowing toward the anode. (HALFWAVE RECTIFICATION)Negative Half
- 101Current will flow through a rectifier then the tube, then another rectifier to the secondary of the transformer. (FULLWAVE RECTIFIER)Positive Half
- 102The current reverses & will flow through the rectifiers that were not used during the positive half of the cycle & also through the tube. (FULLWAVE RECTIFIER)Negative Half
- 103When four rectifiers are used, ___wave rectification is achieved.Fullwave
- 104The final & last section to the x-ray circuit.Filament Circuit
- 105The second part of the x-ray circuit.Secondary Circuit
- 106___ phase allows the potential difference to drop to zero with every change in direction of the current flow.Single Phase
- 107In a ___ wave rectifier circuit, this means the X-ray tube is experiencing no potential difference & is producing no x-ray photon 120 times every sec.Fullwave
- 108The amount of fluctuation in the voltage of the power to an x-ray machine. For x-ray machines, the less ripple, the better.Voltage Ripple
- 109Supplies power to the X-ray tube so that the filament supplies enough electrons by the thermionic emission.Filament Circuit
- 110Supplies power to the X-ray tube so that x-rays are produced.Main Part of X-ray Circuit
- 111The switch that generates the power to the X-ray tube.Main Switch
- 112A remote control device that permits current flow through the circuit.Exposure Switch
- 113Device used to end the exposure at an accurately measured preset time.Timer
- 114This is where the alternating current comes from to power the circuitMain Breaker
- 115This is where you adjust the kVp for the exposure.Autotransformer
- 116This part of the circuit stops the exposure.Timer Circuit
- 117This transformer bumps the voltage up so that the X-ray tube has a very high voltage to make the electrons have enough energy to form x-rays.High-Voltage Step-Up Transformer
- 118This makes the current only go in one direction through the X-ray tube.Four-Diode Rectification Circuit
- 119This variable resistor adjusts the current going to the filament.Filament Circuit Variable Resistor
- 120This transformer steps the voltage down & therefore the current up.Filament Step-Down Transformer
- 121This is where the x-rays are created.X-ray tube
- 122This rotates the anode.Rotor Stator
- 123Suppresses the negative to protect the X-ray tube. Only used in dental.Single Phase One-Pulse (Halfwave Rectified)
- 124Reverses negative pulses to make the positive. Reduces exposure time by 1/2Single Phase Two Pulse (Fullwave Rectified)
- 125Six pulses per cycle. A lot more output.Three Phase Six Pulse
- 126Twelve Pulses per cycle. The greater photon output has greater (higher) energy. Even more outputThree Has Twelve Pulse
- 127Greatest output Lowest Dose to pt. High energy & short exposure timesHigh Frequency
- 128When four rectifiers are used:Full-wave Rectification is achieved
- 129—
Informações
- Descrição
- Fall 2017 Radiologic Technology Physics FlashCards sobre Radiographic Physics- Unit 4: The X-Ray Circuit, criado por Alex Ertmer em 27-09-2017.
- Criado por
- Alex Ertmer · set 2017
- Atualizado
- 11 out 2017
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