BME 520 Multiple Choice - Final
Which of the following is not considered a force?
a. Electrostatic
b. Weak
c. Strong
d. Gravity
e. Electricity ** Answ** e- Electricity is the flow of charge, and is measured in amps (C/s).
Which of the following is not a unit of energy?
a. Erg
b. Joule
c. Watt
d. Calorie
e. eV ** Answ** c- The watt is a unit of power, measured in J/s.
Which of the following would most likely be attracted to an anode?
a. Proton
b. Neutron
c. Electron
d. Positron
e. Alpha particle ** Answ** c- Electron, since it has a negative charge that is attracted to the
positive anode.
Which quantity is the best measure of power?
a. Joule
b. Tesla
c. Watt
d. Coulomb
e. Newton ** Answ** c- Watt is a unit of power, where 1 W= 1 J/s.
,Which of the following is/are likely to have the longest wavelength?
a. Gamma rays
b. Microwaves
c. Radiowaves
d. Ultraviolet
e. Visible light ** Answ** c- Radio waves have the lowest frequencies and longest
wavelengths.
For electromagnetic radiation, which increases with increasing photon energy?
a. Wavelength
b. Frequency
c. Velocity
d. Charge
e. Mass ** Answ** b- Frequency, which is directly proportional to the photon energy
If the distance from a radiation source
is halved, the radiation intensity increases by a factor of:
a. 2^−2
b. 2^−1
c. 2^0
d. 2^+1
e. 2^+2 ** Answ** e- 2^2 (i.e., 4). Halving the distance quadruples the radiation intensity
(inverse square law).
X-ray generators have a power level (kW) of approximately:
a. 0.1
b.1
c. 10
d. 100
,e. 1,000 ** Answ** d- 100 kW is typical of the power of x-ray generators in radiography and
CT.
Which of the following is not a type of x-ray generator?
a. Single phase
b. Double phase
c. Six pulse
d. Twelve pulse
e. High frequency ** Answ** b- There are no double-phase generators.
The purpose of x-ray transformers is most likely to change the:
a. magnetic field
b. electrical voltage
c. power level
d. waveform frequency
e. current intensity ** Answ** b- Transformers change (increase or decrease) voltages.
When a secondary coil has 500 more turns than a primary coil, the ratio of the secondary voltage
to the primary voltage is most likely:
a. 500
b. 500^0.5
c. 1/500
d. 1/500^0.5
e. Depends on AC frequency ** Answ** a- 500. The increase in voltage is directly
proportional to the increase in the number of turns.
Which of the following generators is likely to have the largest waveform ripple?
a. Constant potential
b. High frequency
c. Single phase
d. Six pulse
, e. Twelve pulse ** Answ** c- The ripple on a single phase generator is 100%.
Electrons passing through matter lose energy primarily by producing:
a. bremsstrahlung
b. characteristic x-rays
c. atomic ionizations
d. Compton electrons
e. photoelectrons ** Answ** c- Electrons lose most of their kinetic energy by knocking out
(or exciting) outer shell electrons.
Tungsten is most likely used as an x-ray target because it has a high:
a. physical density
b. electron density
c. electrical resistance
d. melting point
e. ionization potential ** Answ** d- Tungsten can tolerate very high temperatures, which
makes it an attractive target material in x-ray tubes.
The maximum photon energy in x-ray beams is determined by the x-ray tube:
a. current
b. exposure time
c. target material
d. anode-cathode voltage
e. total filtration ** Answ** d- The voltage across the x-ray tube determines the kinetic
energy
imparted to the electrons that are accelerated from the cathode (filament) to the anode (target),
and thereby the maximum x-ray photon energy.
The most likely characteristic x-ray energy (keV) from x-ray tubes used in chest radiography is:
a. 19
b. 33
Which of the following is not considered a force?
a. Electrostatic
b. Weak
c. Strong
d. Gravity
e. Electricity ** Answ** e- Electricity is the flow of charge, and is measured in amps (C/s).
Which of the following is not a unit of energy?
a. Erg
b. Joule
c. Watt
d. Calorie
e. eV ** Answ** c- The watt is a unit of power, measured in J/s.
Which of the following would most likely be attracted to an anode?
a. Proton
b. Neutron
c. Electron
d. Positron
e. Alpha particle ** Answ** c- Electron, since it has a negative charge that is attracted to the
positive anode.
Which quantity is the best measure of power?
a. Joule
b. Tesla
c. Watt
d. Coulomb
e. Newton ** Answ** c- Watt is a unit of power, where 1 W= 1 J/s.
,Which of the following is/are likely to have the longest wavelength?
a. Gamma rays
b. Microwaves
c. Radiowaves
d. Ultraviolet
e. Visible light ** Answ** c- Radio waves have the lowest frequencies and longest
wavelengths.
For electromagnetic radiation, which increases with increasing photon energy?
a. Wavelength
b. Frequency
c. Velocity
d. Charge
e. Mass ** Answ** b- Frequency, which is directly proportional to the photon energy
If the distance from a radiation source
is halved, the radiation intensity increases by a factor of:
a. 2^−2
b. 2^−1
c. 2^0
d. 2^+1
e. 2^+2 ** Answ** e- 2^2 (i.e., 4). Halving the distance quadruples the radiation intensity
(inverse square law).
X-ray generators have a power level (kW) of approximately:
a. 0.1
b.1
c. 10
d. 100
,e. 1,000 ** Answ** d- 100 kW is typical of the power of x-ray generators in radiography and
CT.
Which of the following is not a type of x-ray generator?
a. Single phase
b. Double phase
c. Six pulse
d. Twelve pulse
e. High frequency ** Answ** b- There are no double-phase generators.
The purpose of x-ray transformers is most likely to change the:
a. magnetic field
b. electrical voltage
c. power level
d. waveform frequency
e. current intensity ** Answ** b- Transformers change (increase or decrease) voltages.
When a secondary coil has 500 more turns than a primary coil, the ratio of the secondary voltage
to the primary voltage is most likely:
a. 500
b. 500^0.5
c. 1/500
d. 1/500^0.5
e. Depends on AC frequency ** Answ** a- 500. The increase in voltage is directly
proportional to the increase in the number of turns.
Which of the following generators is likely to have the largest waveform ripple?
a. Constant potential
b. High frequency
c. Single phase
d. Six pulse
, e. Twelve pulse ** Answ** c- The ripple on a single phase generator is 100%.
Electrons passing through matter lose energy primarily by producing:
a. bremsstrahlung
b. characteristic x-rays
c. atomic ionizations
d. Compton electrons
e. photoelectrons ** Answ** c- Electrons lose most of their kinetic energy by knocking out
(or exciting) outer shell electrons.
Tungsten is most likely used as an x-ray target because it has a high:
a. physical density
b. electron density
c. electrical resistance
d. melting point
e. ionization potential ** Answ** d- Tungsten can tolerate very high temperatures, which
makes it an attractive target material in x-ray tubes.
The maximum photon energy in x-ray beams is determined by the x-ray tube:
a. current
b. exposure time
c. target material
d. anode-cathode voltage
e. total filtration ** Answ** d- The voltage across the x-ray tube determines the kinetic
energy
imparted to the electrons that are accelerated from the cathode (filament) to the anode (target),
and thereby the maximum x-ray photon energy.
The most likely characteristic x-ray energy (keV) from x-ray tubes used in chest radiography is:
a. 19
b. 33
