Unit 4

• electromagnetic energy

  energy with electrical and magnetic properties
• who theorized that visible light had both properties in the late 19th century

  James clerk maxwell
• photon


  smallest quantity of electromagnetic energy
• electromagnetic radiation consists of electric and magnetic waves that are

  situated 90 degrees to each other
• a photon is also described as a

  quantum
• a quantum is a

  small bundle of energy
• 2 types of photon radiation

  x-rays and light photons
• photons travel at

  the speed of light
• what type of wave do photons travel as

  sine wave
• how are electromagnetic energies arranged in the electromagnetic spectrum

  in the order of increasing energy
• what are the 3 scales of the electromagnetic spectrum

  frequency, wavelength, and energy
• velocity


  speed of light
• SI unit for speed of light

  (c) 3x10^8 m/s
• amplitude


  intensity identified by height
• how is amplitude measured

  half the range from crest to valley
• wavelength


  distance between two points on a wave
• frequency


  number of wavelengths (rate of rise and fall)
• how is frequency measured

  Hertz (Hz)
• 1 hertz=

  1 cycle per second
• what kind of relationship do wavelength and frequency have

  inversely proportional
• what kind of wavelength results in a high frequency

  short wavelength= high frequency
• what kind of wavelength results in a low frequency

  long wavelength=low frequency
• what kind of relationship do energy and frequency have

  directly proportional
• an increase in energy causes a ________ in frequency

  increase
• a decrease in energy causes a ___________ in frequency

  decrease
• what kind of relationship do energy and wavelength have

  inversely proportional
• increase in energy causes a _________ in wavelength

  decrease
• decrease in energy causes a __________ in wavelength

  increase
• if a wave has a high energy it will have

  a short wavelength and a high frequency
• if a wave has a low energy it will have

  a long wavelength and a low frequency
• radio waves are identified by

  frequency
• radio waves have relatively

  low energy and long wavelength
• wavelengths are measured in

  meters
• MRI what two things to produce images

  radio waves and magnets
• MRI radio frequencies are in the

  upper RF range
• visible light is identified by

  wavelength
• what is the smallest segment of the electromagnetic spectrum

  visible light
• the color with the shortest wavelength

  violet (400 nm)
• Color with longest wavelength

  red (700 nm)
• what type of wavelength does infrared light have

  long