1. What Wavelength Was That?
Examining the Electromagnetic Spectrum
with Hands-On Activities
Mr Hemming

2. Electromagnetic Waves
All travel at the speed of light, 300,000 km /s. (That’s 8 times around the earth in a second!)
All can travel through empty space (a vacuum)
All can be reflected or refracted
The shorter the wavelength the more dangerous they are
They all transmit energy from one place to another

4. Electromagnetic Radiation
The only difference between radio waves, visible light, and gamma-rays is the energy of the photons.
Radio waves have photons with low energies, microwaves have a little more energy than radio waves, infrared has still more, then visible, ultraviolet, X-rays, and gamma-rays.

6. Radio (Low Frequency & Very High Frequency)
Emitted by
Astronomical Objects
Radio Station transmitters
Detected by
Ground based radio telescopes
Radios

7. Microwave Emitted by: Detected by Gas clouds collapsing into stars
Microwave Ovens
Radar Stations
Cell Phones
Detected by
Microwave Telescopes
Food (heated)
Cell phones
Radar systems)

8. Infrared (Near and Thermal)
Emitted by
Sun and stars (Near)
TV Remote Controls
Food Warming Lights (Thermal)
Everything at room temp or above
Detected by
Infrared Cameras
TVs, VCRs,
Your skin

9. Visible Emitted by Detected by The sun and other astronomical objects
Laser pointers
Light bulbs
Detected by
Cameras (film or digital)
Human eyes
Plants (red light)
Telescopes

10. Ultraviolet Emitted by Detected by Tanning booths (A) The sun (A)
Black light bulbs (B)
UV lamps
Detected by
Space based UV detectors
UV Cameras
Flying insects (flies)

11. X-ray Emitted by Detected by Astronomical objects X-ray machines
CAT scan machines
Older televisions
Radioactive minerals
Airport luggage scanners
Detected by
Space based X-ray detectors
X-ray film
CCD detectors

12. Gamma Ray Emitted by Detected by Radioactive materials
Exploding nuclear weapons
Gamma-ray bursts
Solar flares
Detected by
Gamma detectors and astronomical satellites
Medical imaging detectors

13. X-rays and Gamma Rays • Black holes • Active Galaxies • Pulsars
• Diffuse emission
• Supernovae
Gamma-ray bursts
• Unidentified

14. The Multiwavelength Sun
X-Ray UV
Visible
The Multiwavelength Sun
Microwave
Radio
Infrared

15. A CONTEST!!! GXUVIMR RMIVUXG
A Mnemonic for the Electromagnetic Spectrum…
Gamma Rays
X-rays
Ultraviolet
Visible
Infrared
Microwave
Radio
GXUVIMR
RMIVUXG