Rad 125 exam 1 (set b)

What was Roentgen experimenting with when he discovered x-rays?

A cathode ray tube

When was the first radiograph produced?

December 22, 1895

What were early x-ray images created on?

Photographic plates

What were two major dangers of early x-ray use?

Radiation burns and operator electrocutions

What are the three fundamental quantities?

Mass, length, and time

Who was Thomas Edison's assistant who suffered severe radiation injuries?

Clarence Dally

What are examples of derived quantities?

Velocity, acceleration, force, momentum, work, and power.

What is velocity?

A measure of speed

What are examples of derived quantities?

Velocity, acceleration, force, momentum, work, and power

 What is momentum?

Mass of an object × its velocity

What is work?

Force applied to an object × the distance across which it is applied

What is power?

Work divided by the time during which the work is done

What is inertia?

The property of an object with mass that resists a change in its state of motion.

What does the roentgen (R) measure?

Radiation intensity

What does the rad measure?

Radiation absorbed dose

What does the rem measure?

Occupational exposure or dose equivalent

What does the curie measure

Radioactivity

What are the two classifications of radiographic equipment?

Mobile and permanently installed

What components make up the tube head assembly?

Xray tube, collimator, and tube stand

What is the purpose of the tube stand?

To provide mobility to the x-ray tube

What is the purpose of the radiographic table?

To position patients for examinations

What is the purpose of the wall unit?

To allow easily obtained upright examinations

How does time affect radiation exposure?

Minimizing exposure time minimizes radiation dose

How does distance affect radiation exposure?

Increasing distance from the radiation source reduces exposure

Who is associated with the earliest atomic theory

Leucippus

 Who formalized the earliest atomic theory

Democritus

Who developed an atomic theory based on scientific evidence?

John Dalton

Who organized the known elements into the periodic table?

Dmitri Mendeleev

Who discovered the electron?

J.J. Thomson.

What model did J.J. Thomson develop?

The plum pudding model

Who conducted experiments with alpha particles?

Ernest Rutherford

What atomic model did Rutherford propose?

A model resembling a tiny solar system

Who is associated with the modern theory of atomic structure?

Niels Bohr

What unit is nuclear binding energy expressed in?

Megaelectron-volts (MeV)

What unit is electron-binding energy expressed in?

Electron-volts (eV)

What are the two types of atomic interactions in the x-ray tube that produce x-rays?

Characteristic and bremsstrahlung

What formula determines the maximum number of electrons in a shell?

2n²

How many electrons can the K shell hold?

2

How many electrons can the L shell hold?

8

How many electrons can the M shell hold?

18

How many electrons can the N shell hold?

32

What is an element?

The simplest form of a substance that composes matter

What is a molecule?

Two or more atoms bonded together

What is a compound

A combination of elements bonded together

Which 'iso' has the same number of protons?

Isotopes

Which 'iso' has the same number of neutrons?

Isotones

Which 'iso' has the same mass number?

Isobars

What is ionic bonding?

Bonding based on attraction between opposing charges

What is electromagnetic radiation?

An electric and magnetic disturbance traveling through space at the speed of light

What is the speed of electromagnetic radiation?

Approximately 3 × 10⁸ m/s

What properties vary among electromagnetic radiation?

Energy, wavelength, and frequency

What is the order of the electromagnetic spectrum from lowest to highest energy?

Radio → microwave → infrared → visible → ultraviolet → x-rays → gamma rays ( Radio Music is very ugly xcept gospel)

Which has the lowest energy in the electromagnetic spectrum?

Radio waves

Which has the highest energy?

Gamma rays

What is the formula for electromagnetic energy?

E = hf

What happens to energy when frequency increases?

Energy increases

What is the relationship between wavelength and frequency?

They are inversely related

What happens to frequency when wavelength increases?

Frequency decreases

What happens to frequency when wavelength decreases?

Frequency increases

What is the formula relating velocity, frequency, and wavelength?

v = fλ

What formula is used for electromagnetic radiation?

c = fλ

What is wave-particle duality?

Electromagnetic radiation can exhibit properties of both waves and particles

What law describes the decrease in radiation intensity with distance

The inverse square law

Where do x-rays originate?

Through interactions between electrons and atoms

Where do gamma rays originate?

In the nuclei of atoms

What is the major difference between x-rays and gamma rays?

Their origin/source

Which electromagnetic radiations are ionizing according to the PowerPoint?

X-rays and gamma rays

What are two types of particulate radiation?

Alpha and beta particles

What is radioactivity?

The process by which an atom with excess nuclear energy emits particles and energy to become more stable

What is radioactive decay?

The process of an unstable atom emitting particles/energy to regain stability

What is half-life?

The time it takes for half of the remaining atoms in an amount of an element to decay

 If you start with 100 atoms, how many remain after one half-life?

50

If you start with 100 atoms, how many remain after two half-lives?

25

 If you start with 100 atoms, how many remain after three half-lives?

12.5

What is an alpha particle made of?

Two protons and two neutrons

What is the charge of an alpha particle?

Positive

How penetrating are alpha particles?

They have a short range and cannot penetrate most objects

What are beta particles?

Electrons emitted from unstable nuclei

Do beta particles originate from an electron shell?

No

Can beta particles ionize atoms?

Yes

 Can beta particles have a positive or negative charge?

Yes

What is a positively charged beta particle called?

 A positron

Are radio waves ionizing?

No

What is one medical use of radio waves?

MRI

what are microwaves commonly used for?

Cell phone signals and heating food

Is infrared ionizing?

No

What is visible light?

The portion of the electromagnetic spectrum perceived by the human eye as colors

What is ultraviolet commonly associated with in the PowerPoint?

Tanning beds

Is ultraviolet classified as ionizing in this PowerPoint?

No

Are X-rays ionizing?

yes

Are gamma rays ionizing?

yes

Do alpha and beta particles have enough energy to ionize matter?

yes

What is radioactive decay?

The process of an unstable atom emitting particles/energy to regain stability

What is a radioactive atom?

An atom with an unstable nucleus