Chapter 1 RADR 1313

When were x-rays discovered?

November 8, 1895

What type of tube was Roentgen working with in his lab when x-rays were discovered?

Crookes tube

Which term is defined as the instantaneous production of light only during an interaction between a type of energy and some element or compound?

Fluorescence

Barium platinocyanide was the:

Fluorescent material that glowed when the tube was energized

The first radiograph produced by Roentgen, of his wife's hand, required an exposure time of:

15 minutes

The letter x in x-ray is the symbol for:

The unknown

The first Nobel Prize for physics was received in 1901 by:

Wilhelm Roentgen

X-rays were at one time called:

Roentgen rays

Erythema, an early sign of biologic damage due to x-ray exposure, is:

Reddening of the skin

X-rays have which of the following properties?

Electrical and magnetic

The distance between two successive crests of a sine wave is known as:

Wavelength

X-rays used in radiography have wavelengths that are measured in:

Angstroms

The frequency of a wave is the number of waves passing a given point per given unit of time.Frequency is measured in:

Hertz

Which is a correct description of the relationship between the wavelength and frequency of the x-ray photon?

inversely related

A _____ is a small, discrete bundle of energy.

Photon

The speed of light is:

3 x 10^8 meters per second and 186,000 miles per second

When first developed, the branch of medicine using x-rays was called:

Roentgenology

The electrical energy applied to an x-ray tube will be transformed to:

Heat and x-rays

The Greek symbol lambda (lambda) represents the x-ray's:

Wavelength

An angstrom (A) is equal to:

10^-10 meter

X-rays used in radiography have wavelengths ranging from 0.1 to:

1 A

X-rays used in radiography have frequencies ranging from 3 x 10^19 to:

3 x 10^18 Hz

In the formula c = lambda x nu, c represents:

The speed of light

In the formula c = lambda x nu, nu represents:

Frequency

The energy of an individual x-ray photon is measured in:

Electron volts (eV)

An x-ray beam that has photons with many different energies is:

Heterogeneous

X-rays can:

All options are correct

Which unit is derived by multiplying a radiation weighting factor (Wr) for the type of ionizing radiation by the units of absorbed dose?

Equivalent dose

What radiation unit is defined as an expression of the relative risk to humans of exposure to ionizing radiation?

Effective dose

X-rays are invisible.

True

X-rays carry a negative charge that causes ionization.

False

X-ray photons travel at the speed of light in a vacuum.

True

X-ray photons are capable of traveling around corners.

False

X-rays can cause certain substances to fluoresce.

True

X-rays will change direction in the presence of a strong magnetic field.

False

X-rays produce a slight tingling sensation when they enter the body.

False

X-rays cannot be focused with a lens.

True

The joule is the SI unit for the transfer of energy into matter (absorbed dose).

True

It is impossible for x-rays to interact with matter and produce secondary radiation.

False

X-rays can produce ionization of atoms making up cells, causing damage.

True

Since Roentgen's discovery in the late nineteenth century, we have learned an enormous amount about the properties of x-rays.

True

It is the radiographer's responsibility to optimize for radiological protection when imaging patients.

True

Screening for pregnancy is an important task for minimizing unnecessary exposure to a developing fetus.

True