medical imaging quiz 1

The SI unit for activity is

Becquerel

Electron binding energy?

The minimum energy that must be added to an electron is order to remove it from an atom

Ionization

The removal or addition of one or more electrons to a neutral atom

Ionizing radiation produces positively and negatively charged particles as it passes through matter

What does the Adams atomic number control?

The characteristics of an atom

What is excitation?

Raising of an electron to a higher energy

What is an elastic collision?

Momentum is conserved, but kinetic energy is not

Is lead a useful barrier for neutrons explain why

No, because it results in the admission of heavy particles. 30% of tumor volume

What is the traditional unit in the SI unit of exposure in air?

Roentgen

SI - coulombs per kilogram

What is the traditional unit in the SI unit for absorbed dose (patient dose)?

Rad

SI - gray

Also referred to as units of kerma

What is kerma?

Kinetic energy released in matter

Energy is transferred from the photons to the electrons of an atom, moving them into a higher energy shell

What is the traditional unit in the SI unit of occupational exposure (dose equivalent)?

rem

SI - sievert

What is the most common use of rems?

Personnel radiation monitoring

What is the F factor?

The ratio between the number of roentgns (exposure) and the number of rads (energy transfer)

Helps us convert exposure to a absorbed dose

What is the traditional unit in SI unit for radio activity?

Curie

SI - becquerel

What was radioactivity discovered by and when? And what can it involve?

Henry becquerel in 1896

It can involve the emission of particles, electromagnetic radiation (photons), or both

Potential energy

Energy of position

Can X-rays act as both waves and particles?

Yes

Elastic interaction

Gives energy to another electron

Neutrons interact by what two main processes

Recoiling and nuclear disintegrations

The highest electron binding energy of an atom is found in the what shell

K Shell, which is the smallest shell

What is the most favored atom diagram?

Bohr model

The closer the shells are to the nucleus the..?

Tighter bound, they are

Where would an electron with the lowest binding energy be most likely located?

It would be found in the M Shell because it is the farthest away from the nucleus

What is strong nuclear force?

It is the force that holds the nucleus of an atom together

What material is most efficient in absorbing a neutron beam

Hydrogenous materials, such as paraffin wax and polyethylene

Elastic collision

Momentum and kinetic energy are conserved

Kinetic energy

Energy that is caused by its motion in space

What is the SI unit used to measure radiation exposure?

Seivert

Define frequency

The number of waves in a given time period

What is frequency measured?

Cycles per second

Hertz

What is a period

The time between the peaks of waves measured in seconds

Wavelength is

The distance between waves

What is the speed of light?

3 × 10^8 m/s or 3 ×10^10 m/s

In a vacuum the speed of EM radiation is the…?

Speed of light

Equation for speed, wavelength, and frequency

C = λv

Equation for energy of any photon to its frequency

E = hv

H = planks constant (6.62 × 10^ 34 j/sec)

Combined equations for energy and wavelength

E = (hc)/λ

Speed equation

C = λf

How many major quantities are important in radiation physics

There are four

Exposure in air, absorbed dose, dose equivalent occupational exposure, radio activity

Photons

Have no mass and no charge

Particles

Have mass and most have some charge

As the wavelength of light is decreased, its speed is

The same

What are the forms of non-ionizing radiation?

Radio waves, microwaves, terahertz, infrared, light waves, ultraviolet waves

The forms of electromagnetic energy in order of frequency

Radiowaves, microwaves, terahertz, infrared, light waves, ultraviolet, x-ray, Gamma ray

How are wavelength and frequency related?

They are inversely proportional as one increases the other decreases

The higher the frequency the shorter the wavelength