Facts about Facts about photonsphotons

PHOTONS

Smallest quantity of electromagnetic radiation

bundle of energy (AKA quantum)

travels at 186,400 miles per second

x-ray and visible light photons

energy disturbances no mass

have electric and magnetic fields that move in sine waves

ELECTROMAGNETIC RADIATION James Clerk Maxwell discovered both

light and x-rays have electric and magnetic properties

TERMINOLOGY OF A SINE WAVE

AMPLITUDE: 1/2 RANGE FROM CREST TO VALLEY

FREQUENCY: RISE AND FALL OF SINE WAVE (HZ).

ONE HZ IS EQUAL TO ONE CYCLE PER SECOND

WAVELENGTH: DISTANCE FROM ONE VALLEY TO ANOTHER OR ONE CREST TO ANOTHER

FACTS ABOUT “c”, “f” AND LAMBDA C or V = velocity C increases as F(FREQUENCY)

increases As LAMBDA (WAVELENGTH)

increases, F decreases V = F x Lambda C = F X Lambda in electromagnetic

radiation

Match the Units of measurement

HzMeterVolts

Energy Frequency Wavelength

MISCELLENOUS FACTS

80 kVp= energies from 0-80 keV x-rays are emitted from electron cloud

gamma rays emitted from nucleus

DEFINITIONS

Reflection Transmission Absorption Transparent Translucent Opaque

Significant in Radiology

Attenuation Radioopaque Radiolucent

PLANCK’S QUANTUM THEORY Understanding of relationship between

energy and frequency X-ray photons travel at speed of light

and exist with velocity or do not exist at all

photon energy is proportional to photon frequency

Planck’s constant

Application of Planck’s Constant

E(eV)=h(Planck’s constant or constant of proportionality*)x f(photon frequency)