Practical Flashcards
which of the following doesn’t describe(apply to?) experimental measurement :
A. all measurements are approximations- no physical quantity can be measured with perfect certainty; there is always errors in any measurement.
B. repeated measurements of a quantity can stray from the quantity’s true value.
C. the accuracy and precision can be improved when repeating an experiment with random error
D. the accuracy can be improved when repeating the experiment in systematic error
The accuracy can be improved when repeating the experiment in systematic error
Light does not need a medium to propagate. Which of the followings explains why light can travel in empty space:
A. because light is a collection of particles
B. because light is an electromagnetic wave
C. because light reflects and refracts
because light is an electromagnetic wave
What happens is true in endoscopy?
A. it undergoes repeated total internal reflection
B. the core has a lower index of refraction
C. the cladding has a higher index of refraction
It undergoes repeated total internal reflection
Which of the following describe the emission line spectra of atoms
A. emission line spectra consists of wavelengths of light in the visible reigon only
B. hydrogen has the simplest emission of all other elements
C. discrete line spectra are due to the existence of many ground states
D. discrete line spectra are due to interactions with neighboring atoms
Hydrogen has the simplest emission of all other elements
what type of energy is transferred by electromagnetic wave from a hot campfire? A. radiation B. convection C. conduction D. combustion
radiation
what does the continuity law composed of
A. conservation of mass
B. conservation of velocity
C. conservation of energy
conservation of mass
what does the acronym laser stand for?
A- light absorption by stimulated emission for radiation
B- light amplification by stimulated emission for radiation
C- light absorption by spontaneous emission of radiation
D- light amplification by spontaneous emission of emission
light amplification by stimulated emission for radiation
what are the characteristics of laser?
A- coherent, monochromatic, multidirectional
B- noncoherent, monochromatic, multidirectional
C-coherent, multicolored, directional
D- coherent, monochromatic, directional
coherent, monochromatic, directional
the right arrangement of how sound propagate through materials from lower speed to higher speed
A- Liquid, solid, gas
B- Gas, liquid, solid
C- Gas, solid, liquid
D- Solid, liquid, gas
Gas, liquid, solid
Which of these errors couldn’t be controlled in the experiment ?
A) Instrumental error
B) Systematic error
C) Random error
D) Force error
Random error
What is the shortest wavelength in the Balmer series
364nm
What is the name of heat transfer by mass movement of molecules from a place to another
A) Conduction
B) Convection
C) Radiation
Convection
Which of the following is a characteristic of a laser:
A.Monochromatic
B. directional
C. coherent
directional
Arrange the speed of sound from slowest to fastest
A) Gas/liquid/solid
B) Solid/gas/liquid
C) Gas/solid/liquid
D) Liquid/solid/gas
Gas/liquid/solid
What are the properties of light from lasers
A) Coherent, many wavelengths, multidirectional
B) Coherent, many wavelengths, directional
C) Coherent, monochromatic, multidirectional
D) Coherent, monochromatic, directional
Coherent, monochromatic, directional
What does the speed of sound depend on
A) Stiffness & Viscosity
B) Density & Stiffness
C) Density & Viscosity
D) Viscosity & Compressibility
Density & Stiffness
What does acronym laser stand for?
a) Light absorption by stimulated emission of radiation
b) Light absorption by spontaneous emission of radiation
c) Light amplification by stimulated emission of radiation
d) Light amplification by spontaneous emission of radiation
Light amplification by stimulated emission of radiation
what is the correct order of increasing (from slowest to fastest ) the propagation of the speed of sound ?
A) solid, liqiud, gas
B) gas, liquid, solid
C) gas, solid, liquid
D) liquid, gas, solid
gas, liquid, solid
what is the shortest wavelength (in nm) observed in the spectrum of hydrogen in the Paschen spectral series?
a) 97
b) 122
c) 400
d) 820
820
What is the phenomena on which fiber optics are based on
A)reflection modulation
B) Total internal reflection
C) chromatic aberration
D) population inversion
Total internal reflection
What does the speed of sound depend on?
a) stiffness and viscosity
b) compressibility and viscosity
c) viscosity and density
d) stiffness and density
stiffness and density
When does acoustic shadowing occur
a) High attenuation surface
b) Low attenuation surface
c) Low reflection surface
d) High absorptio
High attenuation surface
Which statement best explains the term hyperechoic in the context of ultrasound
a) The image is darker than the surroundings
b) The image is brighter than the surroundings
c) The image is as bright as the surroundings
d) An echo free image
The image is brighter than the surroundings
What is the composition of the Braking X-Rays
a) continous spectrum at a specific frequency
b) Specific spectrum
c) Continuous spectrum at any frequency
d) Radiation of only one energy
Continuous spectrum at any frequency
When the electron hit into the tungsten target, what percentage
of X-rays will be emitted
a) 100%
b) 99%
C) 50%
d) 1%
1%
What is given off the most when electrons hit the tungsten target
a) X-rays
b) Heat
c) Light
d) Sound waves
Heat
Why do we use tungsten as a target for X-ray foundation
a) it is cheap
b) it has a high atomic number
c) it can withstand heat
d) it is shiny
it has a high atomic number
What do photocathodes do in an image intensifier of an x-ray
a) They convert heat to light
b) They convert light to heat
c) They convert light to electrons
d) They convert electrons to light
They convert light to electrons
in the context of MRI, what is the name of the recovery of the
longitudinal magnetization ?
a. TR recovery
b. TE recovery
c. T1 recovery
d. T2 recovery
T1 recovery
2-which of the following represents an example of Static
contrast?
a. MRA
b. Chemical shift imaging
c. Perfusion weighted contrast
d. Diffusion weighted contrast
Chemical shift imaging
within the context of MRI, which design can generate a homogenous magnetic field with the use of 2 circular current loops that are separated by a distance equal to the distances of their radius
a. Solenoid double design
b. Helmholtz pair design
C. Solenoid triple pair design
d. Golay pair design
Helmholtz pair design
when sinc function returns to time domain what is the shape of the graph
a. single frequency
b. sinusoid
c. tophat
d. cosine graph
tophat
how long does T1 recovery last for?
a. a few seconds
b. a few milliseconds
c. a few nanoseconds
d. a few picoseconds
a few seconds
6-What is a key characteristic of MRI imaging?
a) It uses ionizing radiation therefore it is more harmful
b) It does not use ionizing radiation therefore it is more harmful
c) It does not use ionizing radiation therefore it is less harmful
d) It uses ionizing radiation therefore it is less harmful
It does not use ionizing radiation therefore it is less harmful
within the context of MRI, how is it possible to select the slice
wanted with different location and thickness?
a) By using only 1 gradient
b) By increasing magnetic field strength
c) By heating the coils before taking the image
d) By using different gradients together
By using different gradients together
If we selected long TE and short TR, what will the resulting
image be?
a) T1 weighted
b) Useless
c) T2 weighted
d) Proton density weighted
PD
what is nuclear magnetic resonance (NMR)?
a) An electromagnetic coil that measures the energy emitted
back to the environment after its initial absorption by the sample
b) The technique that allows the collection of 2D images by
changing spatial gradients, following a single electromagnetic pulse from a transmitter
c) The measurable changes of magnetic properties of atomic
nuclei by applying an oscillating magnetic field at the resonant frequency of the nuclei
d) A magnetic field whose strength varies systematically over space
The measurable changes of magnetic properties of atomic
nuclei by applying an oscillating magnetic field at the
resonant frequency of the nuclei
What is the spatial gradient?
a. An electromagnetic coll that measures the energy emitted
hack to the environment atter its initial absorotion of the sample
b) The technique that allows the collection or 2U images by
changing spatial gradients, following a single electromagneuc pulse from a transmitter
c. The measurable changes of magnetic properties of atomic
nuclel by applying an oscillating magnetic field at the resonant frequency of the nuclei
d) A magnetic field whose strength varies systematically over space
A magnetic field whose strength varies systematically over space
12- what do you get from a sinusoid after fourier transform is applied in the time domain?
a) Single frequency
b) Top hat
c) Larmor frequency
d) Sinc function
Single frequency
what is true about gradient fields
a) They change the strength of the magnetic field but not the
direction
b) They change the strength of the magnetic field and the
direction
c) They do not change both the strength of the magnetic field and the direction
d) They do not change the strength of the magnetic field but they change the direction
They change the strength of the magnetic field but not the
direction
what is used to obtain an image from K space
a) fourier transform
b) larmor frequency
c) Inverse Fourier transform
d) Gradients
Inverse fourier transform
what forms the basis of fMRI contrasts?
a) t1
b) t2
c) t2*
d) TE
t2*
what is the time interval between 2 successive excitation pulses?
a) TE
b) TR
c) T2*
d) T1
TR
The magnetic moment for a spinning proton is generated by
a) the electric current induced by rotating charge
b) the magnetic field induced by the MRI
c) the spatial gradients
d) the x-ray machine
the electric current induced by rotating charge
gradient magnetic fields generate electric current within the body because
a) The human body is a conductor
b) The human body is a heat transmitter
c) The gradient fields are too strong
d) The human body is an incubator
The human body is a conductor
what is the current measured on a detector coil following excitation and reception
a) RF coil
b) Shimming coil
c) MR signal
d) Deduced signal
MR signal
a static magnetic field is a magnetic field whose intensity
a) changes over space and time
b) changes over space but not time
c) Changes over time but not space
d) does not change over space and time
does not change over space and time
what is the name of the frequency of oscillation that provides maximum energy transfer to the system
a) Resonant frequency
b) Received frequency
c) Reflected frequency
d) refraction frequency
Resonant frequency
what is the name of the center part of the MRI machine
a) door
b) hole
c) bore
d) Pore
e) big circle in the middle
bore
what is the time constant that describes the recovery of the
longitudinal component of net magnetization?
a) T1
b) T2
c) TR
d) TE
T1
What is true about T2 and T2*
a) T2 is faster than T2*
b) T2 is slower than T2*
c) T2 and T2* are the same speed
d) WHATS T2*
T2 is slower than T2*
if RF coils resistance is decreases, what happens to the coil?
a) Sensitivity decreases
b) Sensitivity increases
c) Inductance increases
d) Capacitance increases
Sensitivity increases
within the context of MRI, Short TE and Short TR results in
a) T1 contrast
b) T2 contrast
c) T2* contrast
d) PD contrast
T1 contrast
within the context of MRI, which statement is FALSE?
a) If TR is short and TE is short, it will maximize the T1 contrast and minimize the T2 contrast
b) If TR is long and TE is long, it will minimize the T1 contrast
and maximize the T2 contrast
c) If TR is short and TE is long, the image will be PD weighted
d) If TR is long and TE is short, the image will be PD weighted
If TR is short and TE is long, the image will be PD weighted
What is the minimal number of gradients usually used in MRI
a) 1
b) 2
c) 3
d) 4
3
Which of the following is true
a) Each gradient is relevant to its axis and does not change the magnetic field
b) Each gradient is relevant to its axis and does change the
strength of the magnetic field
c) Each gradient is perpendicular to its axis and does not change the strength of the magnetic field
d) Each gradient is perpendicular to its axis and does change the strength of the magnetic field
Each gradient is relevant to its axis and does change the
strength of the magnetic field
which statement appropriately defines MR signal
a) Electromagnetic coils that create controlled spatial variation in the strength of the magnetic fields (gradient coils)
b) The current measured in a detector coil following excitation
and reception
c) Electromagnetic coils that generate and receive signals (
RFcoils)
d) The current measured in the detector coil after excitation
only
The current measured in a detector coil following excitation
and reception
What is the name of the frequency of oscillation that provides the maximum energy transfer to the system
a) Reflected frequency
b) Resonant frequency
c) Absorbed frequency
d) Rejected frequency
Resonant frequency
which statement best describes the T1 period
a) It is measured in an order of a few seconds
b) It is measured in an order of a few milliseconds
c) It is measured in an order of a few microseconds
d) It is measured in an order of a few nanoseconds
It is measured in an order of a few seconds
what is net magnetization?
a) The amount of energy released by the x-ray machine
b) The sum of magnetic moments of all the atoms
c) The sum of magnetic moments in a hydrogen atom
The sum of magnetic moments of all the atoms
which of the following can be categorized into static contrasts
a) MRA
b) TE
c) T1
d) TR
T1
how can we change the thickness of a slice
a) by changing the slope of the gradient and the same radio frequency can be used to select a different location
b) by using reverse fourier transform
c) by using both an MRI and x-ray machine simultaneously
d) by injecting radioactive isotopes into the patient prior to the
examination
by changing the slope of the gradient and the same radio frequency can be used to select a different location
which function will we obtain if we use inverse fourier transform on a sinc function
a) sinusoid
b) single frequency
c) top hat
d) fourier transform
top hat
a short TR and a long TE will give a
a) non-usefull image
b) T1
c) T2
d) PD
non-usefull image
which of the following creates a stron magnetic field that can generate a homogenous magnetic field
a) Golay pair
b) Hemholtz pair
c) Solenoid double
d) Solenoid single
Hemholtz pair
MRI uses
a) non ionizing energy
b) ionizng energy
c) partially ionizing energy
d) lasers
non ionizing energy
which statement best describes the term ‘excitation’
a) receiving electromagnetic energy from a sample at its
resonant frequency
b) receiving electromagnetic energy from a sample at its
reflected frequency
c) sending electromagnetic energy to a sample at its absorbed
frequency
d) sending electromagnetic energy to a sample at its resonant frequency
sending electromagnetic energy to a sample at its resonant frequency
how can a strong magnetic field, which can be generated with minimal electrical power requirements, be created
a) by using cryogens to cool the MRI scanner room
b) by cooling the X-ray machine
c) by cooling the electromagnets to near absolute zero
d) by cooling the electromagnets to room temperature
by cooling the electromagnets to near absolute zero
what happens if we increase R and C
a) the sensitivity will decrease
b) the sensitivity remains the same
c) The sensitivity will increase
d) The sensitivity is so sensitive
the sensitivity will decrease
What do you get from a sinusoid after forier transform is applied in the time domain?
a. single frequency
b. Top hat
c. Larmor freq
d. sinc function
single frequency
Which is true about gradient fields?
a. they change the strength of the magnetic field but not the direction
b. they change the strength and direction of the magnetic field
c. they do not change the strength, they only change the magnetic field direction
they change the strength of the magnetic field but not the direction
What is used to get an image from k space?
a. Forier transform
b. inverse forier transform
c. both forier transform and inverse forier transform
inverse forier transform
What forms the basis of fMRI BOLD contrast?
a. T1
b. T2
c. T2*
d. MRA
T2*
What is the time interval between 2 successive excitation pulses?
a. TE
b. T2
c. TR
d. T1
TR
The magnetic moment for a spinning proton is generated by
a. the electric current induced by rotating charge
b. the magnetic field induced by the MRI
the electric current induced by rotating charge
Gradient magnetic fields generate electric current within the body because
a. the human body is a conductor
b. the human body is a incubator
c. the gradient magnetic fields are too strong
the human body is a conductor
What is the purpose of the gradient coils?
a. to cause the MR signal to become spatially dependent in a controlled fashion
b. to cause the MR signal to become spatially independent in a controlled fashion
c. to cause the F coil to become spatially dependent in a controlled fashion
d. to cause the RF coil to become spatially independent in a controlled fashion
to cause the MR signal to become spatially dependent in a controlled fashion
What is the current measured on a detector coil following excitation and reception?
a. MR signal
b. RF coil
c. shimming coil
d. transmitter coil
MR signal
A static magnetic field is a magnetic field whose intensity
a. does not change over space but changes over time
b. does not change over space nor time
c. does not change over time but changes over space
d. changes over space and time
does not change over space nor time
What is the name of the frequency of oscillation that provides maximum energy transfer to the
system?
a. resonant frequency
b. absorbed frequency
c. armor frequency
resonant frequency
J.J Thompson’s experiment showed that?
a. cathodes give out negatively charged particles
b. cathodes give out positively charged particles
c. Anodes give out - charged particles.
cathodes give out negatively charged particles
Which of the following cant be true?
a. n=1, 1=0, ml =1, ms=1/2
b. n=2, I=1, ml = 0, ms=-1/2
c. n =3. I= 2, ml= -1, ms =-1/2
d. n=5, 1=3, ml=0, ms=1/2
n=1, 1=0, ml =1, ms=1/2
Which of the following wavelengths has the highest energy of a photon?
a. 500 lambda
b. 300 lambda
c. 800 lambda
300 lambda
According to de Broglie, what’s the order of lambda from the shortest to longest:
a. airplane - bullet - proton - electron
b. bullet - airolane - proton - electron
c. airplane - bullet -electron - proton
airplane - bullet - proton - electron
What is the name of the center part of MR..
a. bore
b. hole
c. door
d. core
bore
Which one of the following will give you a physical base quantity?
a. M^(-1) L^(2) T^(1)
b. M^(0) L^(0) T
M^(0) L^(0) T
The visible spectrum wavelengths are.
a. 200- 400 lambda
b. 400- 600 lambda
c. 350 - 750 lambda
350 - 750 lambda
If you increase the voltage across an x-ray tube to 100 k Which of the following is true?
a. the minimum energy of the x-rav spectrum = 100 kV
b. the maximum energy or the x-ray spectrum= 100 kV
c. energy will not change
the maximum energy or the x-ray spectrum= 100 kV
Why do we choose tungsten as a target for x-ray foundation!
a. it is cheap
b. it has high atomic number
c. it does not get heated quickly
it has high atomic number
Braking X- rays give you
a. continuous spectrum
b. specific spectrum
continuous spectrum
What do photocathodes do in an image intensifier of an x-ray?
a. they convert x-ray to light
b. they convert light to x-ravs
c. they convert light to electrons
they convert light to electrons
What is the time constant that describes the recovery of the longitudinal component of net magnetization:
a. T1
b. T2
c. T2*
d. PI
T1
Which gives you velocity of sound in order (from low to high)
a. solid liquid gas
b. gas liquid solid
c. gas solid liquid
gas liquid solid
Which of the following is true?
a. nucleus contains protons and neutrons
b. some. not all, matter is made of atoms
c. electrons are not affected ov electric magnetic force
nucleus contains protons and neutrons
which is true about T2 and T2*?
a. T2 faster than T2*
b. T2 slower than T2*
c. they are the same
T2 slower than T2*
What is the composition of x-rays?
a. Specific spectrum
b. Continuous spectrum
Continuous spectrum
If RF coil s resistance is decreased, what happens to the coil?
a. Sensitivity (Q) increases
b. Sensitivity (Q) decreases
c. Inductance (L) and capacitance(C) increases
d. Capacitance (C) increases
Sensitivity (Q) increases
In the context of MRI short TE and TR means what?
a. T1 contrast
b. T2 contrast
c. T2* contrast
d. PD contrast
T1 contrast
Which of the following about MRIs true?
a. If TR Is Short. TE is short. It will maximize the TI contrast and minimie the T2 contrast
b. If TR is long, TE is long, it will minimize the T1 contrast and maximize the T2 contrast
If TR Is Short. TE is short. It will maximize the TI contrast and minimie the T2 contrast
What is the relationship between attenuation coefficient and the atomic number of Compton Effect
a. u is independent of z
b. u is proportional to z
c. u Is proportional to z^2
d. u is proportionalto z^3
u is independent of z
What’s the minimal number of gradients usually used in MRI
a. 1
b. 2
c. 3
d. 4
3
What is true regarding MRI gradient?
a. Each gradient is relevant to its axis and does not change the strength of the magnetic field
b. Each gradient is relevant to its axis and changes the strength of the magnetic field
c. Each gradient is perpendicular to the axis and changes the strength of the magnetic field
d. Each gradient is perpendicular to the axis and does not change the strength or the magnetic field
Each gradient is relevant to its axis and changes the strength of the magnetic field
Which one of the following is right about accurate and precise.
a. In accurate measurement. the value is not the same as true value
b. The accuracy of the measurement depends on the instrumentthacis used
c. In precise measurement, the measurement does not give near identical values
d. Scientists want precise measurement but not accurate
The accuracy of the measurement depends on the instrumentthacis used
What is the name of the frequency of oscillation that provides the maximum energy transfer to the system
a) Reflected frequency
b) Resonant frequency
c) Absorbed frequency
d) Rejected frequency
Resonant frequency
which statement best describes the T1 period
a) It is measured in an order of a few seconds
b) It is measured in an order of a few milliseconds
c) It is measured in an order of a few microseconds
d) It is measured in an order of a few nanoseconds
It is measured in an order of a few seconds
what is net magnetization?
a) The amount of energy released by the x-ray machine
b) The sum of magnetic moments of all the atoms
c) The sum of magnetic moments in a hydrogen atom
The sum of magnetic moments of all the atoms
which of the following can be categorized into static contrasts
a) MRA
b) TE
c) T1
d) TR
T1
how can we change the thickness of a slice
a) by changing the slope of the gradient and the same radio frequency can be used to select a different location
b) by using reverse fourier transform
c) by using both an MRI and x-ray machine simultaneously
d) by injecting radioactive isotopes into the patient prior to the
examination
by changing the slope of the gradient and the same radio frequency can be used to select a different location
which function will we obtain if we use inverse fourier transform on a sinc function
a) sinusoid
b) single frequency
c) top hat
d) fourier transform
top hat
a short TR and a long TE will give a
a) non-usefull image
b) T1
c) T2
d) PD
non-usefull image
Which constant depends on magnetic field strength and type of tissue to realign spin with external magnetic field?
a. T1
b. T2
c. TR
d. TE
T1
An incident rav trom air to glass has an angle of 30. find the angle atter it passes through the glass
a. 56 away from the normal
b. 50 towaras the normal
c. 18 away from the normal
d. 18 towards the normal
18 away from the normal
Comparing to λ red photon a blue photon has
a. A blue photon has longer λ, less frequency, less energy
b. A blue photon has longer λ, high frequency, higher energy
c. A blue photon has shorter λ, less frequency, less energy
d. A blue photon has shorter λ, higher frequency, higher energy
A blue photon has shorter λ, higher frequency, higher energy
When using high power densitv laser of ultraviolet wavelenath some chemical bonds can be broken, causing local heating. This process called
a. Photochemical
b. Photo-coagulation
c. Photo- vanorization
d. General heating
Photochemical
If the TR= 100 and the TE= 12 what Is the contrast?
a. T1
b. T2
c. PD
d. T2*
PD
What’s the longest wavelength in balmar series
656 nm
Which of the following is true regarding the line spectrum?
a. Bhor’s model of the atom couldn’t explain the line spectrum or H atom
b. The line spectrum emitted by all heated sollds, liquids, and dense gases
c. The line spectrum of heated low density gases emits light at specinic wavelengths
d. The line spectrum emits light at all wavelengths
The line spectrum of heated low density gases emits light at specinic wavelengths
Farsightedness use:
Positive power of foca/llenst
In the context or MRI, what is the name or the recovery or the longitudinal magnetization :
a- TR recovery
b- TE recoverv
c- T1 recovery
d- T2 recovery
T1 recovery
Acoustic shadowing
High attenuation surface.
What does the right-hand rule determine
it determines the angular velocity
Within the context of MRI. which design can generate a homogenous magnetic field with the use of 2 circular current loops that are separated by a distance equal to the distances or their radius
a-solenoid double design
b-Helmholtz pair design
c- solenoid triple pair design
d- golay pair design
Helmholtz pair design
What is magnetic moment?
the torque exerted on a magnet
When sinc function returns what haopens to the time domain?
Top hat
What is the longest wavelength of the palmers series?
656
Which Instrument will ave vou homogenous pair, the radius = the distance between them, pair of loops
helmholtz pain
T1 Recovery duration?
few seconds
What is considered a true statement
a- ionizing radiation has higher energy and frequency and wavelength than non-ionizing radiation
b- ionizing radiation has higher energy and frequency and lower wavelength than non-ionizing radiation
c- ionizing radiation has lower enerav and frequency and higher wavelength than non-ionizing
radiation
ionizing radiation has higher energy and frequency and lower wavelength than non-ionizing radiation
How is MA is related to Z in Compton scattering?
MA IS independent from Z
Which of the following wave lengths has the highest energy of a photon?
2-800
b-400
c-500
d-700
400
What is the order or density Is the speed or sound raster!
solid, liquid, gas
Bernoull’s equation depends on:
mass conservation, energy conservation
Whats the relation between Compton and attenuation coeticient:
attenuation coefficient is dependent of Z
Arrange propagation speed from the lowest to the highest: a- solId, liquid, gas b- gas, liquid solid c- liquid, gas, solid d. gas, solid, liquid
solId, liquid, gas
Which of the followina is a static contrast
a- MRA
b- T1
c- TE
d- T2
T1
and
T2
Why is the emission spectrum is a characteristic of the material and can serve as a type of fingerprint to identify gases?
a- because all gases emit the same wavelength of line spectrum
b-only light at certain wavelenaths are emitted
c- they are unique
only light at certain wavelenaths are emitted
What is a characteristic of MRI imaging:
- uses ionizing radiation
- uses non-ionizing radiation.
uses non-ionizing radiation
What is the longest wavelength in Balmer series?
2-420
b-656
c-1850
656
What’s the wavelength range of visible light?
750nm to 380nm
In MRI, how is it possible to select the slice with different location and thickness?
Different gradient
long TE, short TR? What is the image?
we cannot make image
what is NMR?
Nuclear Magnetic Resonance (NMR): The measurable changes in magnetic properties of atomic nuclei induced by the application of an oscillating magnetic field at the resonant frequency or the nuclei
What is the “spatial gradient”?
special gradient is magnetic felid whose strength varies systemically over the space.
Systematic errors ead to the reduction of
a -Precession in measurements
b- Significant figures in measurements
c- Accuracy in measurements
Accuracy in measurements
What is the composition of x-rays produced by “braking” type?
a- a small number or delinea energies
b- continuous spectrum
c- radiauon or on one enera onoton
d- specific spectrum
continuous spectrum
what explains the hyperchoic in context of ultrasound?
a- image darker than the surroundings
b- image brighter than the surroundings
c-image as bright as the surroundings
d-image without echoes (echo free)
image brighter than the surroundings
In MRI, what is the minimum amout of gradients used?
3
In MRI, what Is the time interval between successive excitation pulses?
A. TR
B. TE
C. T1
TR
In MRI, what is the time constant that depends on magnetic field strength
and type of tissue and indicates time taken to realign with the external
magnetic field?
A. T2
B. T1
C. TE
D. TR
T1
In the context of MRI, short TE and short TR create which type of image?
A. T1 weighted
B. T2 weighted
C. PD weighted
D. T2* weighted
T1 weighted
What is true regarding T2 and T2*?
A. T2 decay is faster than T2* decay
B. T2 decay is slower than T2* decay
C. they are the same
D. T2* decay is double the T2 decay
T2 decay is slower than T2* decay
The ideal static magnetic field has:
A. an intensity that does not change over space only
B. an intensity that does not change over space or time
C. an intensity that changes over time and space
an intensity that does not change over space or time
The frequency of oscillation that provides maximum energy transfer to the system is:
a. resonant frequency
b. reflected
c. repeated
d. resting
resonant frequency
The frequency of oscillation that provides maximum energy transfer to the system is:
a. resonant frequency
b. reflected
c. repeated
d. resting
resonant frequency
The relationship between the attenuation coefficient of Compton
scattering and the atomic number (Z):
A. the attenuation coefficient of Compton scattering is proportionate to Z
B. the attenuation coefficient of Compton scattering is proportionate to Z12
C. the attenuation coefficient of Compton scattering is proportionate to Z^3
D. it is independent of Z
it is independent of Z
What is true about atoms?
A. not all matter is composed of atoms
B. different atoms have the same nuclear compositions
C. the nucleus contains protons and neutrons
the nucleus contains protons and neutrons
What changes the speed of sound?
A. wavelength
B. frequency
C. amplitude
D. medium
medium
What generates the magnetic moment in spinning protons?
A. the electric current which is induced by rotating charge
B. the movement of its internal magnetic field
the electric current which is induced by rotating charge
What is the current measured in a detector coil following excitation and
reception?
MR signal
What is the central tube of MRI called?
A. core
B. bore
C. RF coil
bore
In radio frequency (RF) coils, if the resistance is decreased, what
happens to the coil sensitivity (Q)?
A. the sensivity increases
B. the sensitivity decreases
the sensiviv increases
What is true regarding MRI gradients?
A. each gradient is relevant to its axis and changes the strength and direction
of the magnetic field
B. each gradient is relevant to its axis and only changes the strength of the
magnetic field
C. each gradient is perpendicular to the axis and changes the strength of the
magnetic field
each gradient is relevant to its axis and only changes the strength of the magnetic field
If TR= 2000 and TE=30 what will the image be?
A. T1 weighted
B. T2 weighted
C. T2* weighted
D. PD weighted
PD weighted
What is the percentage of ultrasound reflected in “air-fat”boundary? Zair= 400 , Z fat= 1.3x10^6
A. 99%
B. 1%
99%
The speed of sound wave depends on the :
A. medium
B. frequency
medium
When measuring the mass quantity of the salt once using the balance 16.43 (g)
A. 16.430 ‡ 0.001 g
B. 16.43 ‡ 0.01 g
C. 16.34 g
16.43 ‡ 0.01 g
Which of the following describes MRI?
A. if TR is short, TE is short, it will maximize the effect of T1 differences and and minimize the effect of T2 differences
B. if TR long, TE is long, it will minimize the effect of T2 differences and maximize the effect of T1 differences
C. short TR, short TE minimize the effect of T1 differences and maximize the T2 differences
D. long TR, short TE minimize the effect of T1 differences and maximize the T2 differences
if TR is short, TE is short, it will maximize the effect of T1 differences and and minimize the effect of T2 differences
Short TE and short TR in MRI?
A. T1 weighted image
B. T2 weighted image
D. PD weighted image
T1 weighted image
What best describes the intensity of the ideal static magnetic field ?
A. doesn’t change over space nor time
B. changes over space but doesn’t over time
C. doesn’t change over space but change over time
D. changes over space and time
doesn’t change over space nor time
in the context of MRI what represent the time between successive
excitation pulses?
A. T1
B. T2
C. Tr
D. Te
Tr
In context of mri, the ideal static magnetic field is characterized by in
terms of the intensity ?
A. changes over space and time
B. does not change over space and time
C. changes over space , but not over time
D. changes over time, but not space
does not change over space and time
In the MRI context. what is the name of the current measured in the detector after excitation and reception
Mr signal
Which best describes the atom:
The nucleus has protons and neutrons.
What is differences between T2 wT2*
A. T2 is faster than T2*
B. TR is slower than T2*
C. T2 has the same velocity of T2*
TR is slower than T2*
if the RF coil’s resistance decreases, what happens to the coil?
A. the sensitivity (Q) increases
B. the sensitivity (Q) decreases
C. the inductance (L) and the capacitance(C) increase
D. the capacitance (C) increases
the sensitivity (Q) increases
in x-ray tube, the reason could decrease the minimum wavelength in the continuous spectrum is
A. the kinetic energy of the incident electron is increased
B. target is a higher atomic number
C. target is a lower atomic number
D. something about using a thin target rather than thick target
the kinetic energy of the incident electron is increased
In context of MRI. What is the frequency of oscillation that provides
maximum energy:
A. armor frequency
B. resonant frequency
resonant frequency
)If the thermal conductivity k increased by a factor of 5 , what change happens to the rate of heat loss ?
A. increases by a factor of 5
B. decreases by a factor of 5
C. Increases by a factor of 2
D. 1/2
increases by a factor of 5
What is the highest frequency if a hydrogen atom absorbed energy and
was transmitted from a lower energy state to a higher energy state)
A. n:9 > n:6
B. n:6 > n:3
C. n:8 > n:5
D. n:13 > n:10
n:6 > n:3
A patient is given a corrective lense of +1.75 diopter. What does the
patient suffer from.
A. Too short focal length
B. image forms after the retina
C. it is corrected with diverging lens
D. patient has myopia
image forms after the retina
according to broglie, whats the order if wavelength from shortest to
longer?
A. bullet, proton, electron, photon
B. photon, electron, proton , bullet
C. bullet, photon , proton , electron
bullet, proton, electron, photon
The magnetic moment for a spinning proton is generated by
A. The electric current induced by rotating charge
B. The magnetic field induced by the MRI
The magnetic field induced by the MRI
which of the following is true regarding MRI gradient?
A. Each gradient is relevant to its axis and does not change the strength of
the magnetic field.
B. Each gradient is relevant to its axis and changes the strength of the
magnetic field
C. Each gradient is perpendicular to the axis and changes the strength of the
magnetic field
D. Each gradient is perpendicular to the axis and does not change the
strength of magnetic field.
Each gradient is relevant to its axis and changes the strength of the
magnetic field
what is the MLT formula for a and b
V= a+bt
M^OL ^1T^-1 , M^OL^1T1-2.
In compton scattering whats the relation between M and z
M is independent of Z
What is the process or heat transter ov the mass movement of molecules from one place to another?
a. Convection
b. Conduction
c. Radiation
d. Combustion
Convection
What will haopen to flow it the viscosity is doubled and the length is halved
a. 1
b. 2
c. 4
d. 8
1
What is a technique used in MRI with the off-resonance excitation pulse to saturate the MR signal from large molecules?
a. X-ray
b. Manti resonan
c. Magnetization transfer imaging
d. MR signal
Magnetization transfer imaging
What is a visual description of how one or more quantities vary over space?
a. gradient
b. Image
c. Resonance
d. Echo
Echo
If TR= 3000ms and TE= 15, what type of image is created?
a. T1
b. T2
c. T2*
d. PD
PD
What will happen if vou decrease the resistance of the MR.
a. Increase of Q
b. Decrease of Q
c. Increase capacitance
d. Increase capacitance and energy
Increase of Q
Which coil is effective for close regions and produces a sensitive image only in that region!
a. Volume coil
b. Surface coil
c. Shimming arrav coll
d. Multifunctional coil
Surface coil
Which of the following is a factor that aftects the speed of sound
a. Frequency
b. Wavelength
c. Medium
d. Amplitude
Medium
What is a nucleus with NMR properties called?
a. Proton
b. Neutron
c. Spin
d. Magnet
Spin
An electron hits a target anode, which produces x-rays of 70eV energy. That means
a. Breaking x-rav with a minimum energy of 70eV
b. Breaking x-rav with a minimum energy of 70eV
c. Characteristic x-rav with a minimum enerav of 70eV
d. Characteristic -ray with a mean energy of 70eV
Breaking x-rav with a maximum energv of 70eV
If the intensitv of a sound beam remains unchanged and the area is halved the power. the initial power is Po
a. 0.5 Po
b. 2 Po
c. 4 Po
d. Po
0.5 Po
Bernoull’s equation is a consequence of.
a. Energy conservation
b. Mass conservation
c. heat conservation
d. Pressure conservation
Energy conservation
If TR is short, and TE is short, then the image formed is
a. PD
b. T2*
c. T1
d. No image
T1
How is MA is related to Z in photoelectric effect?
a. Independent
b. Dependent Z
c. Dependent Z^2
d. Dependent Z^3
Dependent Z^3
Which type of ultrasound artifacts has a high level of attenuation:
a. Lateral cystic shadowing
b. Acoustic enhancement
c. Acoustic shadowing
d. Reverberation artifacts
Acoustic shadowing
Which one or the following is a representation or K-space:
a. Sinc function
b. Top hat
c. Single trequenc
d. sinusoid
Sinc function
A measure of the strength of a magnetic field over an area or space
a. Flux
b. Bo
c. Spin
d. C
Flux
The ability to store electric charge:
a. Flux
b. Bo
c. Spin
d. C
Spin
What is the dimensional formula of KE?
a. M^2 L T^2
b. M^-2 L T^2
c. M L^2 T^-2
d. M L T
M L^2 T^-2
What is the direction of the static magnetic field?
a. Horzonal
b. Vertical
c. Longitudinal
D Perpendicula
Longitudinal
What does armor trequency depend on
a) numper or gradients
b) number or spins In spin system
c) strength of the magnetic field
d) the angular of the magnetic field
strength of the magnetic field
What is the purpose of the gradient coils?
a. to cause the MR signal to become spatially dependent in a controlled fashion
b. to cause the signal to become spallally Independent In a controlled fashion
c. to cause the Ar coll to become spatially dependent in a controlled tashion
to cause the MR signal to become spatially dependent in a controlled fashion
ov what factor doe sthe blood flow change if the viscosity is doubled and the length of the vessel is halved
a) 1
b) 2
c) 4
d) 8
1
What is the x-radiation production or braking process?
Continuous spectrum of energies
Which type or Interaction with matter causes me X-ray pnoton to disappear and removes an electron from the atom
a) photoelectric effect
b) comoton scattering
c) pair production
a) elastic scattering
photoelectric effect
what Is the process or Dolling on electron out or the milament or an xray tube
thermionic emissior
After Fourier transformation sinusoid becomes :
A. Double frequenci
B. Too hat
C. Single frequency
D. Sinc function
Single frequency
What factor affects the speed of sound
a) frequency
b) wavelength
c) medium
d) amplitude
medium
Tr= 700 Te= 25
A) T1
B) T2
C) T2*
D) PD
T1
What is the central tube in mri called?
A-Bore
B- Core
C- Door
Bore
What are the properties of an ideal fluid?
a. Non viscous, laminar Incompressible
b. Non viscous, tulorent. compressible
Non viscous, laminar . Incompressible
In the context of MRI what best describes the use of TR and TE?
Short TR and short Tr will maximize T1 diferences and Minimize T2 diferences
In MRI, Why is gradient switching can generate small electric currents that have the potential to stimulate nerve and muscles, or alter function or implanted devices
A) because human body acts as conductor
b) because human body acts as insulator
because human body acts as conductor
what forms a basis bold contrast in fmri?
a t contrast
b) t2* contrast
C) pd contrast
t2* contrast
if TR is short TE is long, what will be the weighting of MRI image?
a) T2 weighted
b) T1 weighted
c) PD weighted
d) Not useful
Not useful
what describes a nucleus in the context of MRI
a) a nucleus with either angular momentum or magnetic moment
b) a nucleus with both angular momentum and magnetic moment
c) a nucleus in NMR
d) a nucleus in NMR depends on the gradient magnetic field
a nucleus with both angular momentum and magnetic moment
TR=short, TE=short
a) T1-weighted
b) T2-weighed
c) PD-weighted
d) not useful
T1-weighted
whar spectrum does the X-ray effect when add filter
a) low energy
b) high energy
High energy
ln context of MRI which is a mathematical technique(s) used to convert raw data from k-space to image space
a) Fourier transfom
b) Inverse fourier transform
c) a and b
d) Fourier transform and Bloch equation
Inverse Fourier transform
a short TR and a long TE will give
A) T1
B) T2
C) PD
D) non useful image
non useful image
In context of MRI, what is true regarding shimming coils
A) Shimming coils are always left on
B) Shimming coils are adjusted for each patient
Shimming coils are adjusted for each patient
Within the context of MR. what is the best describe of ideal static magnetic field
a) does change over space but not over time
b) Does not change over space nor time
c) Does change over time nor space
d) Does change over space and time
Does not change over space nor time
What is the amount of significant figures in the following measurement: weight : 78.45 Kg
a) 2
b) 3
c) 4
d) 5
4
What is the dimensional formula of KE. KE = 1/2 mv^2 where m is the mass and v is the velocity?
A) ML^-2T^-2
B) ML^2T^-2
C) ML^-1T^-2
D) M^0LT
ML^2T^-2
What is the time interval berween 2 successive excitation pulse
a) TE
b) T2
c) Tr
d) T1
Tr
The Ideal static magnatic field has :
a) an intensity that doesnt change over space on
b) an intensity that doesnt change over space or time
c) an intensity that does change over space or time
an intensity that doesnt change over space or time
he magnatic moment or spinning proton is generated by:
a) the electric current induced by rotating charge
b) the magnatic feild induced by the MRI
the electric current induced by rotating charge
If RF coils resistance decreases what happen to the coil ?
a) the sensitivity Q increase
b) the sensitivity Q decrease
c) the inductance (L) and capacitance (C) increase
d) the capacitance Increase
the sensitivity Q increase
What is the current measured on a detector coil followina excitation and reception
a) MR signals
b) RF coil
c) shimming coil
d) transmitter coil
MR signals
