Radiation Production and Characteristics and Imaging Equipment and Maintenance

0.005Sv___________microSv

5,000

A linear accelerator uses a magnetron to generate which of the following?

Microwave radiation for acceleration

The photoelectric effect was explained by Albert Einstein. Which of the following conditions BEST describes this interaction?

All or nothing complete absorption

The half-value layer (HVL) of a particular x-ray beam is 2.5 mm Al. If the initial intensity is 100 mR, what would be the approximate intensity after passing through 7.5 mm Al?

12.5 mR

Which of the following is non-ionizing particulate radiation?

None

In nuclear medicine, PET imaging utilizes the annihilation of positrons with electrons. This process results in the production of:

Two photons at 180° with 511 keV each

In radioactive decay, what is the daughter nuclide when a parent undergoes positron emission?

Lower Z by 1, same A

Which generator system is known for providing the most consistent voltage with minimal ripple?

High-frequency

In a parallel circuit with resistors of 8Ω, 16Ω, and 24Ω connected to a 220V source, what is the current through the 8Ω resistor?

27.5 A

Which type of electromagnetic radiation is used in cancer treatment for its ability to kill cells?

Gamma ray

A technologist observes that the radiographic image has a short scale of contrast. Which of the following interactions is primarily responsible for producing this characteristic?

Photoelectric effect

Which of the following is the main health risk associated with prolonged exposure to ultraviolet light?

Skin cancer

In the manual film processing sequence, which chemical is responsible for stopping the development action immediately?

Acetic acid

Which of the following BEST describes the function of the focusing cup in an x-ray tube?

Converges and concentrates electrons to the focal spot

In terms of voltage ripple, which of the following systems has the highest percentage of ripple?

Single-phase full-wave

During radioactive decay, a parent nuclide undergoes negative beta decay. Which of the following correctly describes the transformation?

A neutron converts to a proton with electron emission and antineutrino

A radiographer uses a technique of 80 kVp and 200 mAs with a 3-phase 6-pulse generator. What is the heat unit calculation for a single exposure?

21,600 HU

A technologist is performing a radiograph using 70 kVp and 50 mAs. If the distance is doubled, what new mAs would maintain the same optical density?

200 mAs

Which fundamental particle has a positive charge?

A. Alpha

B. Proton

C. Neutron

D. Positron

Proton

Which particle is emitted during alpha decay?

Alpha particle

Which particle is identical to an electron but has a positive charge?

Positron

Which of the following is equal to the atomic number of a neutron?

0

Which particle is emitted during beta-minus decay?

Negatron

Which of the following is another name for a beta-minus particle?

Negatron

Which of the following particles has the smallest mass?

Negatron

Which of the following is the composition of an alpha particle?

2 protons and 2 neutrons

Which particle is emitted during beta- plus decay?

Positron

Which subatomic particle determines the chemical element of an atom?

Proton

Which of the following is the main product of alpha decay?

Helium nucleus

Which particle has the same mass as a proton but no electric charge?

Neutron

Which of the following is the voltage ripple percentage typically associated with a 3-phase, 6-pulse generator?

14%

Which of the following is the typical voltage ripple for a high-frequency generator?

Less than 1%

Which generator system would be most appropriate for a mobile x-ray unit due to its compact size and efficiency?

High-frequency

Which particle is involved in chemical bonding?

Electron

Which of the following is the charge of an alpha particle?

+2

Compared to a single-phase full-wave generator, how many times more pulses per second does a 3-phase, 6-pulse generator produce?

Three times as many

If a 3-phase, 6-pulse generator is operating at 60 Hz, how many pulses does it produce per second?

360 pulses per second

Which of the following does an X-ray tube rating chart primarily indicate?

The safe operating limits for the tube to prevent damage

Which of the following type of radiation involves the emission of an electron from the nucleus?

Beta radiation

Which of the following is a component of both the proton and neutron?

Quark

Which of the following is the main function of the cathode in an X-ray tube?

To produce electrons

Which of the following element makes up 98-99% of the filament in an X-ray tube?

Tungsten

Which of the following is the purpose of thorium in the X-ray tube filament?

To prolong X-ray tube life and To enhance electron emission

Which of the following material is used for the focusing cup in an X-ray tube?

Nickel

Which of the following is the main function of the focusing cup in an X-ray tube?

To concentrate electrons

Which of the following is the composition of the target of the focal spot in an X-ray tube?

90% Tungsten, 10% Rhenium

Why is rhenium added to the tungsten target in an X-ray tube?

To increase mechanical strength and To enhance X-ray production

Which of the following is the main purpose of the target in an X-ray tube?

To emit X-rays

Which factor is typically not represented on an X-ray tube rating chart?

Patient size

Which of the following percentage of the filament in an X-ray tube is typically thorium?

1-2%

Which of the following is the primary advantage of using tungsten for the X-ray tube filament?

High melting point

The X-ray tube rating chart helps to avoid:

Exceeding the heat capacity of the tube

Which of the following role does the glass envelope play in the X-ray tube?

To maintain a vacuum

Which material is used to enhance the durability of the filament in an X-ray tube?

Thorium

Which of the following will happen if the exposure time is too long for a given mA and kVp according to the X-ray tube rating chart?

The tube will overheat and may be damaged

Which of the following is one of the purpose of adding thorium to the tungsten filament?

To enhance electron emission

Which of the following material is used for the target in an X-ray tube to withstand high temperatures?

Tungsten

Which of the following is the purpose of the high melting point of the tungsten target?

To withstand high temperatures during X-ray production

Why is a vacuum necessary inside the X-ray tube?

To prevent electron scattering

Which of the following is the main benefit of using rhenium in the X-ray tube target?

Increased durability

When using an X-ray tube rating chart, which parameter should be adjusted if a chosen mA and exposure time combination is unsafe?

Decrease the mA

Which of the following is the purpose of the high atomic number of tungsten in the X- ray tube target?

To increase X-ray production efficiency

Which part of the X-ray tube is directly involved in the generation of X-rays?

Focal spot

Which of the following is the primary function of a transformer?

To change the voltage

Which principle does a transformer primarily operate on?

Electromagnetic induction

Which of the following type of transformer increases the voltage from primary to secondary winding?

Step-up transformer

In a step-down transformer, which winding has more turns?

Primary winding

Which of the following is the main component of an autotransformer?

A single winding that acts as both primary and secondary

Which type of transformer is used to decrease current?

Step-up transformer

Which of the following does the turns ratio of a transformer determine?

Voltage ratio between primary and secondary windings

Which of the following best describe mutual induction?

The process of inducing voltage in one coil due to the changing current in a nearby coil

In a transformer, if the primary winding has 100 turns and the secondary winding has

200 turns, Which of the following type of transformer is it?

Step-up transformer

Which of the following is the role of the core in a transformer?

To provide a low-resistance path for the magnetic flux

Which type of transformer uses a single winding for both primary and secondary functions?

A. Step-up transformer

B. Step-down transformer

C. Autotransformer

D. Isolation transformer

Autotransformer

How does an increase in the number of turns in the secondary winding of a transformer affect the secondary voltage?

It increases the secondary voltage

In characteristic interaction, which electron is involved in the collision that produces X-rays?

Inner orbital electron

During Bremsstrahlung interaction, the filament electron interacts with which part of the target atom?

Nucleus

Which of the following happens to the inner orbital electron in a characteristic interaction?

It is ejected from the atom

Which type of X-ray production involves the deceleration of high-speed electrons?

Bremsstrahlung interaction

In Bremsstrahlung interaction, which causes the X-ray photons to be emitted?

Deceleration of electrons near the nucleus

Which interaction is responsible for the continuous spectrum of X-ray radiation?

Bremsstrahlung interaction

Which of the following is the outcome when a filament electron collides with an inner orbital electron during characteristic interaction?

The inner orbital electron is ejected

Which type of X-ray production results in X-rays with discrete energy levels?

Characteristic interaction

Which of the following role does the nucleus play in Bremsstrahlung interaction?

It decelerates the electron, causing emission of X-rays

Which of the following type of power loss in a transformer is due to the resistance of the windings?

Copper loss

Which loss in a transformer is caused by the alternating magnetic field in the core material?

Hysteresis loss

How can copper losses in a transformer be minimized?

Using thicker conductors

Which method is used to reduce eddy current losses in transformer cores?

Laminating the core

5mrad______________microrad

None

150rad_____________mrad

None

500microrad____________mrad

0.5

Rotation of the rotor is made through the principle of:

Electromagnetic induction

During Compton scattering, with which part of the atom do X-rays interact?

Outermost electron

Which of the following is the primary mechanism for X-ray absorption in soft tissues at diagnostic energy levels?

Compton scattering

Which of the following is produced during pair production when an X-ray interacts with the nuclear electric field?

A positron and an electron

Which of the following is the outcome of photodisintegration in radiation therapy?

Dissociation of the nucleus

Which interaction results in the production of secondary radiation?

Compton scattering

Which interaction increases with higher atomic number and lower X-ray energy?

Photoelectric effect

In which interaction does the X-ray photon completely disappear?

Photoelectric effect

Which of the following is the energy threshold for pair production to occur?

1.02 MeV and 1,022 keV