1st Semester Semi-Final Flashcards
Which statement is false for the Doppler-effect?
A) The frequency of the radiation decreases if the source approaches the observer
B) The frequency of the radiation decreases if the source moves away from the observer
C) The frequency of the reflected radiation increases if the reflecting surface moves towards the detector
D) the observed frequency increases if the source of radiation moves towards the observer
A)The frequency of the radiation** **decreases if the source approaches the observer
Which light source is not based on Luminescence?
A) Sodium Lamp
B) Mercury Vapour Lamp
C)Tungsten Filament Lamp
D) Ruby Laser
C) Tungsten Filament Lamp
What does the maximum point of the spectrum of luminescent radiation depend on?
A) Temperature of emitting material
B) Chemical composition of emitting material
C) Concentration of emitting material
D) Thickness of emitting material
B) Chemical composition of emitting material
41) Which is not a Synonym of the radiation over thermal radiation?
A)”cold light”
B) Luminescence
C) Light emission due to relaxation from the excited state
D) FRET
D) FRET - _F_luorescence Resonance Energy Transfer
88) What is not true for the attenuation coefficient?
A) it depends on the quality of the absorbent material
B) It depends on the wavelenght of the radiation
C) It is the reciprocal of the half value thickness
D) It depends on the density of the absorbent material
C) It is the reciprocal of the half value thickness
89) Which is not a part of the Scintillation Counter?
A) Scintillation crystal
B) Photomultiplier
C)Discriminator
D)Luminescent Screen
D) Luminescent Screen
90) What is visual acuity?
A) The smallest light intensity which we can detect
B) The reciprocal of the smallest distance which can be resolved
C) The ratio of the normal limiting angle of view to the actual limiting angle of view.
D) The difference of the smallest and largest power of the eye
C) The ratio of the normal limiting angle of view to the actual limiting angle of view.
**1) in the case of deterministic damage **
A) The probability of the damage depends on the dose
B) There is a threshold dose and the severity of the damage doesn’t depend on the dose
C)There is a threshold dose and the severity of the damage depends on the dose
D) There is no threshold dose
C) There is a threshold dose and the severity of the damage depends on the dose
3) The eyepiece of a microscope forms a…
A) Diminished, erect, virtual picture/image
B) Magnified, erect, virtual picture/image
C) Diminished, inverted, real picture/image
D) Magnified, inverted, real picture/image
D) Magnified, inverted, real picture/image
4)In the equation the value of the is
C) Depends on the frequency of the radiation, the material and the density of the absorbent
6) What is not true about linear attenuation coefficient?
A) Depends on the material of the absorbent
B) Depends on the wavelength of the radiation
C) Depends exponentially on the thickness of the absorbing layer
D) Depends on density of the absorbing material
D)Depends on density of the absorbing material
7) Which is not a particle radiation?
A) Alpha Radiation
B) Beta Radiation
C) Gamma Radiation
D) Neutron Radiation
C) Gamma Radiation
9) The absorbed dose
A) The amount of charge absorbed in unit mass
B) The amount of energy arrived through the radiation in unit mass
C) The amount of energy absorbed in unit mass
D) The amount of positive charges created by radiation in unit mass
C) the amount of energy absorbed in unit mass
10) What kind of isotopes can be used for “in vivo” diagnostic purposes ?
A) Alpha emitting
B) Negative beta-emitting
C) Gamma-emitting
D) Neutron-emitting
C) Gamma emitting
16) Which radiation is not electromagnetic radiation?
A) Ultrasound
B) Gamma radiation
C) X-radiation
D) Light
A)Ultrasound
18) The irradiance in the case of thermal radiation
A)Inversely depends on the temperature of the body and the environment
B) Depends on the 4th power of the temperature of the environment
C)Linearly depends on the temperature of the body
D)Depends only on the temperature of the body
D) Depends only on the temperature of the body
19) In the case of negative beta-decay the mass number
A) Decrease by 1
B) Increases by 1
C) Remains the same
D) Decreases by 2
C) Remains the same
Which is not a part of the scintillation counter?
A) Scintillation crystal
B) Photomultiplier
C) Discriminator
D) Luminescent screen
D) Luminescent screen
72) When is the Doppler frequency shift maximal?
A) If the flow velocity and the US beam are parallel
B) If the flow velocity and the US beam enclose a small angle
C)If the flow velocity and the US beam encloses a large angle
D) If the flow velocity and the US beam are perpendicular
A) If the flow velocity and the US beam are parallel
The reflection of Ultrasound
A) Is fundamental in aquiring the diagnostic information
B)Decreases the sharpness of the image, do it should be avoided
C) Depends only on the stiffness of the reflecting surface
D)Depends only on the angle of incidence of the ultrasound
55) Choose the wrong statement.
A) An open themodynamic system may exchange energy with its environment
B) An open thermodynamic system may exchange matter with its environement
C) The closed thermodynamic system may exchange only matter with its environment, but no energy
D)The isolated thermodynamic system may exchange neither energy nor matter with its environment.
54) Which of the following quantities is intrensive?
A) Charge
B) Entropy
C) Density
D) Amount of substance
C) Density
85) What is the function of the intergral discriminator?
A) Pulses below the threshold can pass
B)Pulses above the threshold can pass
C) Pulses falling into the channel can pass
D)Pulses below the lower threshold and above the higher threshold can pass
B) Pulses above the threshold can pass
Mechanisms of luminescence; fluorescence;phosphorescence; kasha’s rule
spontaneous emission of light, when electrons return back to ground state from excited state (de-excitation)/radiation emitted by matter in excess of thermal radiation /”cold light”.
Two types of Luminescence?
Fluorescence and phosphorescence
How does Fluorescence get produced?
Singlet state? Triplet state?
Singlet state: opposite spin of electron
Triplet state: ground state has electrons that have the same spin as the excited electrons.
When is Beer-Lambert law applicable ?
A) Diluted Solutions
B) gases
C) everything
D) solid material
A) Diluted Material

The differential discriminator…
A) lets pulses under the threshold pass on
B) lets pulses above the threshold pass on
C) lets pulses falling to the channel pass on
D) lets pulses falling out of the channel pass on
C) lets pulses falling to the channel pass
The absorbance
A) proportional with the intensity of the incident beam
B) it is the magnitude of attenuation expressed in %
C) the ten based logarithm of the ratio of incident and transmitted
D) the natural logarithm of the ratio of the incident and transmitted.
C) the ten based logarithm of the ratio of the incident and transmitted.

What does the (focal) accomodation of the eye mean?
A) the farthest distance from the eye where the point is still sharp
B) the closest distance from the eye where the point is still sharp
C) the differenece of the smallest and largest power of the eye
D) the reciprocal of the focal distance of the lens
What is true for the background noise pulse in the scintillation counter?
A) the amplitude of them are always smaller than the amplitude of the signal impulses
B) with discriminators we can discriminate them from the signal pulses
C) with discriminators we can decrease their rate to the signal pulses
D) their main source is the discriminator
c) with discriminators we can decrease their rate to the signal pulses.
The induced emission
A) produce population inversion in lasers
B) the energy of the excited state is transferred to heat
C) the emitted photons have the same phase and the inducing photons
D) the wavelength of the emitted photons is bigger than the wavelength of the of the inducing photon.
The value of the attenuation coefficient dependes on:
A) the intensity of the radiation
B) the thickness of the absorbent material
C) the density of the absorbent material
D) the time of the irradiation
The intergral discriminator…
a) lets pulses under the threshold pass on
b) lets pulses above the threshold pass on
c) lets pulses falling into the channel pass on
d) lets pulses falling out of the channel pass on
b) lets pulses above the threshold pass on.
What does E mean in the beer-lambert law?
a) molar extinction coefficient
b) specific transmittance
c) transmittance
d) attenuated intensity
a) molar extinction coefficient
What does visual acuity mean?
a) the smallest light intensity which we can detect
b) the reciprocal of the smallest distance which can be resolved
c) the ratio of the normal limiting angle of view to the actual limiting angle
d) the difference of the smallest and largest power of the eye
The induced emission is triggered by:
a) high enough temperature
b) spontaneously emitted photons
c) pumping energy
d) exciting photons
What is the meaning of coherence?
a) the beam of photons is convergent.
b) the beam of photons is parallel
c) the energy of the beam of photons is concentrated into a small spot
d) the phase of the photons is identical
Phosphorescence:
A) occurs during transition from singlet excited (S1) state to triplet (T1) state
B)occurs during transition from triplet (T1) state to singlet ground (S0) state.
C) occurs during tranistion from singlet ground (S0) state to Triplet (T1) state.
D) occurs during transition from singlet excited (S1) state to singlet ground (S0) state.
What is the meaning of coherence?
A) the beam of photons is parallel
B) the beam of photons is convergent
C) the energy of the beam of the photons is concentrated into a small spot
D) the phase of photons is identical.
In the equation j= je^-μx … μ
a) depends only on the quantity of absorbing material
b) depends on the nature of radiation and on the light intensity
c) depends on frequency of radiation and on quality and density of absorbing material
d) depends on the size of the object, the frequency of radiation and on quality density of the absorbing material.
(?)
What does the photoeffect mean?
A) This means that electric current increases the temperature of metal filaments
B) this means that electrons are released from the metal upon irradiation by electromagnentic radiation.
C) this means light emission by discharge tube upon voltage difference
D) this means that electrons generate light pulses in luminescent screen.
What does the position of the maximum point of the luminescence spectrum depend on?
A) Temperature of the emitting substance.
B) Chemical composition of the emitting substance
C)concentration of the emitting substance
D) thickness of the emitting substance
How is the absorbance altered if the concentration of the sample is decreased to one half? (All the other conditions remain the same).
A) Decreased to 1/4 of its original value
B) Increased twofold
C)Decreased to one-half
D) increased fourfold
c) decreased to one-half (1/2)
6) What is the meaning of choherence ?
A) the phase of waves are the same
B) Light beams are convergent
C) The energy of a light beam is concentrated into a small spot.
D) The energy of a light beam is concentrated into a short pulse.
2) The velocity of an electron emitted from an alkali metal due to illumination depends on…
A) …the intensity of the illuminating light.
B) …the wavelength of the illuminating light
C)…both the intensity and the wavelength of the illuminating light.
D)…neither the intensity nor the wavelength of the illuminating light.
b) the wavelength of the illuminating light
How much is the absorbance if the sample transmits 10% of the incident light?
a) 10
b) 1
c) 2,302
d) 0,1
Which light source is not based on the luminescence process?
A) Sodium Lamp
B) Tungsten Lamp
C) Laser light
D) Mercury lamp
Tungsten lamp -light source based on thermal radiation
Stimulated emission is induced by…
a) …pumping the energy
b) …spontaneously emitted photons
c) …exciting photons.
d) …suitbaly high temperature.
b)…spontaneously emitted photons
Not:
a) pumping the energy -population inversion -LASERS
b) exciting photons
c) …suitably high temperature.
What types of bonds connect the atoms within the water molecule?
a) hydrogen
b) covalent bond
c) van der Waals interaction
d) salt bridge
b) covalent bond
asking us what bond types are with in the water molcules
not :
a) hydrogen bond - outside the water molecule—binding to water molecules together or
c) van der waals interactions –
Why is the sky blue?
a) Because red light is refracted more, thus mostly blue light reaches our eyes.
b) Because blue light is scattered more.
c) Because the thermal radiation of the sun (equivalent to the black body of 6000K ) is the most intensive in the blue wavelength interval.
d) because the light of lower photon energy (red)nis absorbed more while traveling the surface, this mostly blue light reaches our eyes.
6) select the right statement on population inversion.
a) it can only be generated by laser light
b) lower energy levels are more populated
c) one of the excitation energy levels is more populated
8) which one of the following is not the property of laser light?
a) coherent.
b) monochromatic
c) convergent
d) typically has high intensity
c) convergent
the shape of a water molecule resembles
a) an icosahedron
b) a cube
c) a tetrahedron
d) a pentahedron
Which is not necessarly the property of laser light?
a) Monochromatic
b) High energy
c) Coherent
d) Parallel rays
Wwhat is the ratio of the incident and transmitted intensity, if the optical density is 2?
a) 2
b) 100
c) 20
d) e^2
Plot the emission spectrum of Bremsstrahlung at two accelerating voltages in the same coordinate system
Give the change of the optical density, if both the concentration and the thickness of the solution are decreased by half ( other circumstance are unchanged)?
a) reduced to 25%
b) doubled
c) reduced to half
d) unchanged
a) reduced to 25%
In case of a guven material, the maximum point of which spectrum is at the longest wavelength?
a) excitation spectrum
b) fluorescence emission spectrum
c) phosphorescence emission spectrum
d) absorption spectrum
c) phosphorescence emission spectrum
Which one is electromagnetic radiation?
a) Alpha radiation
b) Beta radiation
c) Gamma radiation
d) Neutron radiation
c) Gamma radiation (?)
Gamma Radiation is generated in which part of the atom?
a) in the nucleus
b) in an inner electron shell
c) in an outer electron shell
d) both in the outer electron shell and the nuclues.
a) in the nucleus- paired effect/ pair production(?)
not
b) in an inner electron shell - photoeffect
c) in an outer electron shell- compton effect
d) both in the outer electron shell and the nuclues.

Which one can’t be part of an absorption spectrophotometer?
a) light source
b) monochromator
c) scintillation crystal
p) photomultiplier
what is the exctinction(absorbance), if the fraction of incident light intensity that passes through is 10%?
a) 10
b) 1
c) 2,302
d) 0,1
Find the one with different meaning?
a) extinction
b) absorbance
c) transmittance
d) optical density
c) transmittance
The image in the retina is…
a) real, diminished and upright
b) real, diminished and inverted
c) virtual, magnified and upright
d) virtual, diminished and inverted
B) real, diminished and inverted
The unit of the molar exctinction
9) visual acuity means:
a) the smallest light that we can still sense
b) the reciprical of the shortest distance we can still distinguish
c) the ratio of the normal limiting angle view (1minute) to the actual limiting angle of view(⍺) in percents.
d) the difference of the largest and the smallest power of the eye
Which statement is not correct?
a) linear attenuation coefficient is proportional to the density of the absorbant.
b) the linear attenuation coefficient is proportional to the effective atomic number of the absorbant.
c) the mass attenuatuion coefficient is proportional to the wavelength of the radiation.
d) the mass attenuation coefficient is proportional to the density of the absorbant.
Which statement is true? the optimal setting of the discrimination level:
a) the baseline is set to 0V
b) the signal to noise ratio is zero
c) the signal to noise ratio has a maximum
d) the noise is zero
In a radioactive sample, the number of atoms that decay in a unit time depends on:
a) the temperature
b) the type of the emitted radiation
c) the place of radioactive drug in the body
d) the number of the radioactive atoms in the sample.
Parts of the scintillation counter, except;
a) scintillation crystal
b) photomultiplier
c) discriminator
d) luminescent screen
d) luminescent screen
Which statement on Bremsstrahlung is not correct?
a) it has a line spectrum
b) it is generated at every accelerating voltage
c) the emitted power is proportional to the square of the accelerating voltage.
d) the emitted power is proportional to the anode current.
Which statement on the thermal radiation is incorrect?
a) the emissivity of the absorbance black body is maximal.
b) the absorptivity of the absolute black body is 100%
c) Every body emits thermal radiation depending on the temperature of the environement.
d) the ratio of emissivity and absorptivitity of a body at a given wavelength and temperature is constant.
C) every body emits thermal radiation depending on the temperature of the environment.
The voltage pulse in the coulter counter is proportional with:
a) the number of cells passing through capillary in a unit time
b) the volume of the sample
c) the volume of the cell passing through the capillary
d) the baseline of the integral discriminator
1) Give the optical denisty, if the transmittance is 20%.
A) 0.7
B) 0.2
C) 0.5
D)0.3
2) What is the minimal energy for pair production?
A) 512keV
B) 1204keV
C) 1.024MeV
D)512eV
C) 1.024MeV
3)Which of the following is not a part of a scintillation counter?
A) Scintillation crystal
B) Photoelectron multiplier
C)Discriminator
D) Monochromator
D) Monochromator
4) What gives the main intrinsic and extrinsic bakground noises in a scintillation counter
A) Extrinsic: the universe radiation; Intrinsic: because the K+ isotopes of humans.
B) Extrinsic: the K+ isotopes of humans; Intrinsic: because the electric part of the counter
C) Extrinsic: natural depot of radon of the Earth; Intrinsic because the scintillation crystal.
D) Extrinsic: the universe radiation; Intrinsic: because the PM tube.
D) Extrinsic: the universe radiation; Intrinsic: because the PM tube.
5 Which of the following contributes to the image formation of the eye with the greatest optical power?
A) Retina
B) Lens
C) Cornea
D) Aqueous humor
6) Choose the wrong answer.
A) The life time of fluorescence is longer than that of phosphorescence.
B) Phosphorescence is spontaneous photonemission from a metastable level.
C) The emission spectrum of phosphorescence is shifted toward the less photonenergies relative to that of fluorescence.
D) Fluorescence is spontaneous photonemission from permitted electron transition.
A) the life time of fluorescene is longer than that of phosphorescence.
7) select the right statement on population inversion.
A)The population of energy levels can be described by Boltzmann-distribution.
B) Lower energy levels are more populated
C) one of the excitation energy levels are more populated.
D) It can only be generated by laser light.
C) one of the excitation energy levels are more populated
8) Which of the following would be a due distance between the resonator mirrors fro the 632nm He-Ne Laser?
A) 31.6 cm
B) 63.2nm
C) 30cm
D) 40 nm
A) 31.6cm
9) What induces the induced emission in laser?
A) Heat
B) Photons
C) High Voltage
D) electrons
B) Photons
10) According to Abbe’s Priniciple…
A)…red light enables greater resolution than blue.
B)…blue light enables greater resolution than red
C)…the energy of the scintillation photon.
D)…a vritual image is formed in the microscope.
B)…blue light enables greater resolution than red.
10 becquerel is the activity of that radioactive preparation
A) in which 10 decays occur in a minute.
B) in which 10 decays occur in a second
C) in which 10 decays occur in an hour
D)in which 1 decay occurs in 10 seconds
B) in which 10 decays occur in a second
Resting Potential of the cells
A) Is time dependent trans-membrane potential.
B) can be calculated from Donnan model.
C) is apporximately +60mV
D) depends on the concentration gradient and permeability constants of ions.
D) Depends on the concentration gradient and premeability constant of ions
The difference between X-ray and light is that
A) The speed of propagation of X-ray is higher.
B) the wavelength of X-ray is bigger
C) the frequency of X-ray is bigger
D) X-ray is generated in the nuclei of atoms.
c) the frequency of x-ray is bigger
11) which statement is not correct for the attenuation coefficient?
A) Attenuation coefficient depends on the atomic number of the absorber
B) Attenuation coefficient depends on the wavelenght of radiation
C) Attenuation coefficient is the reciprocal of half value thickness
D) Attenuation coefficient depends on the density of the absorber
C)attenuation coeffient is the reciprocal of half value thickness
12) During photoeffect
A) The intensity of current is inversely proportional to the light frequency
B) the energy of incident photons covers the work function of electrons
C) ions are ejected from metals
D)positrons are emitted by cations
B) the energy of incident photon covers the work function of electrons
Blood is