Questão 1
Questão
Which of the following is an advantage of a permanent magnet MRI system
Responda
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Very heavy
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Low operating costs
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Fixed field strength
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Limited field strength
Questão 2
Questão
Which of the following types of MRI magnet is known as the Classical electromagnet
Responda
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Resistive magnet
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Superconducting magnet
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Permanent magnet
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Distractive magnet
Questão 3
Questão
Which of the following is a disadvantage of a resistive magnet MRI system
Responda
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Easy coil maintenance
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Low cost
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High power consumption
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None of the above
Questão 4
Questão
The type of MRI magnet that is produced by cooling a current down to 4 degrees Kelvin is known as a
Responda
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Distractive magnet
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Permanent magnet
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Resistive magnet
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Superconducting magnet
Questão 5
Questão
The type of MRI magnet that allows the highest field strengths is a
Responda
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Resistive magnet
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Superconducting magnet
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Iron core magnet
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Permanent magnet
Questão 6
Questão
Coils used to correct imperfections in the magnetic field are known as
Responda
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RF coils
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Surface coils
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Gradient coils
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Shim coils
Questão 7
Questão
The type of magnet that is produced by permanently magnetizing a ferromagnetic substance is known as a
Responda
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Resistive magnet
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Electromagnet
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Superconducting magnet
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Permanent magnet
Questão 8
Questão
In clinical MRI, permanent magnets can be produced to operate up to what field strength
Responda
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0.3 tesla
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0.5 tesla
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1.0 tesla
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1.5 tesla
Questão 9
Questão
Which of the following is a disadvantage of using a permanent magnet in clinical MRI
Questão 10
Questão
Which of the following materials is most commonly used to produce a permanent magnet
Questão 11
Questão
The type of magnet that is produced by passing an electrical current through a conductor is known as a
Questão 12
Questão
The rule that is used to determine the direction of the magnetic field in an electromagnet is known as
Responda
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Ohm's Law
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Right hand thumb rule
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Left hand thumb rule
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None of the above
Questão 13
Questão
In clinical MRI, resistive magnets usually operate at what field strength
Questão 14
Questão
Which of the following is an advantage of using a resistive magnet for clinical MRI
Responda
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High power consumption
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Low capital cost
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Low field strength
-
None of the above
Questão 15
Questão
The law that is used to determine the amount of resistance in a conductor is known as
Responda
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Newton's Law
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Ohm's Law
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Faraday's Law
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Murphy's Law
Questão 16
Questão
The type o f magnet that is produced by removing resistance from a conductive wire is known as
Responda
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Resistive magnet
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Reactive magnet
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Permanent magnet
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Superconducting magnet
Questão 17
Questão
The wire used to create the main magnetic field in a superconducting magnet is known as
Responda
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Aluminum-Tiobium
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Iron sulfite
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Copper-tungsten
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Niobium-Titanium
Questão 18
Questão
The external magnetic field in a superconducting magnet is said to be what type of magnetic field
Responda
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Static
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Kinetic
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Gradient
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Resistive
Questão 19
Questão
The wire used in the main magnetic field of a superconducting magnet has its resistance removed by cooling it to a temperature of
Responda
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-452 degrees Fahrenheit
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0 degrees Celsius
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269 degrees Kelvin
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None of the above
Questão 20
Questão
The liquids used to cool the wire in the main magnetic field of a superconducting magnet are known as
Responda
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Neon gases
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Plasma
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Cryogens
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None of the above
Questão 21
Questão
The specific liquids used to maintain low temperatures in the superconducting wire are
Responda
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Titanium and Niobium
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Hydrogen and Neon
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Halon and Oxygen
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Helium and Nitrogen
Questão 22
Questão
The device used to store and transport cryogenic liquids is known as a
Responda
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Thermos
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Dewar
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Barrel
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None of the above
Questão 23
Questão
In a superconducting magnet, the sudden loss of superconductivity is known as a
Responda
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Squelch
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Slouch
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Screech
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Quench
Questão 24
Questão
In an MRI system, the magnetic field that extends outside the bore of the magnet is known as the
Responda
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Extended field
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Outer field
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Fringe field
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In field
Questão 25
Questão
In clinical MRI, superconducting magnets usually operate at field strengths from
Responda
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0.15 to 0.3 tesla
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0.5 to 2.0 tesla
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2.5 to 4.0 tesla
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Over 4 tesla
Questão 26
Questão
In clinical MRI, which of the following is an advantage of using a superconducting magnet
Responda
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High field strength
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Shorter scan times
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Low power consumption
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All of the above
Questão 27
Questão
In clinical MRI, which of the following is a disadvantage of using a superconducting magnet
Responda
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High capital costs
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High fringe field
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High cryogenic costs
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All of the above
Questão 28
Questão
The method used to contain the main magnetic field within the scan room is known as
Responda
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Shimming
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Shielding
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Fringing
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None of the above
Questão 29
Questão
The method of MRI field containment that uses steel lining in the walls of the magnetic room is known as
Responda
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Active shimming
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Passive shielding
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Active shielding
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Passive shimming
Questão 30
Questão
The method of MRI field containment that uses additional magnets outside the cryogenic area of the magnet is known as
Responda
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Active shimming
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Passive shielding
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Active shielding
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Passive shimming
Questão 31
Questão
The process of adjusting coils to improve the homogeneity of the external magnetic field is known as
Responda
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Strengthening
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Fringing
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Shielding
-
Shimming
Questão 32
Questão
Each shim coil requires its own power supply
Questão 33
Questão
The type of shimming that is achieved by placing a ferrous material around the main magnet is known as
Responda
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Passive shimming
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Passive shielding
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Active shimming
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Active shielding
Questão 34
Questão
The type of shimming that is achieved by adjusting the electrical current in specialized coils is known as
Responda
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Passive shimming
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Passive shielding
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Active shimming
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Active shielding
Questão 35
Questão
The homogeneity of the external magnetic field is measured in what type of unit
Responda
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Tesla per cm
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Part per million (ppm)
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Gauss per meter
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Megahertz
Questão 36
Questão
In clinical MRI, the homogeneity of the magnet should be at least
Responda
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1 tesla per cm
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10 parts per million
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0.5 gauss per meter
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32 magahertz
Questão 37
Questão
The type of coils used to change the strength of the magnetic field inside the bore of the magnet are known as
Responda
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RF coils
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Shim coils
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Surface coils
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Gradient coils
Questão 38
Questão
In a gradient coil, the amplitude of the gradient slope is determined by what factor
Questão 39
Questão
How many gradient coils are there in a clinical MRI system
Responda
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1 pair
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2 pairs
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3 pairs
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4 pairs
Questão 40
Questão
Gradient strength is measured in what form of unit
Questão 41
Questão
The time it takes for a gradient coil to reach its peak strength is known as
its
Responda
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Repetition time
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Echo time
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Rise time
-
Inversion time
Questão 42
Questão
Coils that are used to transmit and receive radio frequencies are known as
Responda
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RF coils
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Shim coils
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Gradient coils
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Surface coils
Questão 43
Questão
The type of RF coil that encompasses the entire anatomy to be scanned is known as
Responda
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Surface coil
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Phased array coil
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Volume coil
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Gradient coil
Questão 44
Questão
The type of RF coil configuration that uses a pair of coils perpendicular to each other to transmit and receive signal is known as a
Responda
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Surface coil
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Phased array coil
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Quadrature coil
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Shim coil
Questão 45
Questão
The type of RF coil configuration that uses a series of independent coils to create one image is known as a
Responda
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Surface coil
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Phased array coil
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Quadrature coil
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Gradient coil
Questão 46
Questão
The type of RF coil configuration that is used to image anatomical structures close to the surface of the patient is known as a
Responda
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Surface coil
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Quadrature coil
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Phased array coil
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Shim coil
Questão 47
Questão
Mutual induction between the RF transmitter and the RF receiver is known
as
Responda
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Isolation
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Deisolation
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Coupling
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Decoupling
Questão 48
Questão
Isolating the RF transmitter from the RF receiver is known as
Responda
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Deisolation
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Isolation
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Coupling
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Decoupling
Questão 49
Questão
The computer that performs the complex calculations necessary to reconstruct MRI images is known as the
Responda
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Array processor
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RF amplifier
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Gradient amplifier
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Shim cabinet
Questão 50
Questão
The device in the MRI system that supplies power to the gradient coils is known as the
Responda
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Array processor
-
RF amplifier
-
Gradient amplifier
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None of the above
Questão 51
Questão
The device in the MRI system that supplies power to the RF transmitter coils is known as the
Responda
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Array processor
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RF amplifier
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Gradient amplifier
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None of the above
Questão 52
Questão
Prior to each scan, the process of prescanning performs which type of calibration
Responda
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Adjusts the transmit gain
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Adjusts the receive attenuation
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Sets the center frequency
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All of the above
Questão 53
Questão
The calibration of transmit gain during the prescan process determines which factor
Responda
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RF output necessary to produce a 90 degree flip angle
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The exact resonant frequency
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The necessary amount of signal needed to create an image
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None of the above
Questão 54
Questão
The process during the prescan that determines the amount of signal that is received is known as
Questão 55
Questão
The process during prescan that fine tunes the resonant frequency is known
as
Questão 56
Questão
How many miliseconds are there in a minute