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

2. Electromagnetic Spectrum
The full range of frequencies, from radio waves to gamma rays, that characterizes light
The electromagnetic spectrum can be expressed in terms of energy, wavelength, or frequency. Each way of thinking about the EM spectrum is related to the others in a precise mathematical way.
The wavelength equals the speed of light divided by the frequency or lambda = c / nu

3. Electromagnetic Radiation
Electromagnetic radiation can be described in terms of a stream of photons, each traveling in a wave-like pattern, moving at the speed of light and carrying some amount of energy.
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. Scaling the Spectrum Activity
Helps to explain the electromagnetic spectrum and dispels some of the common misconceptions.
Paper and pencil project that requires the use of math skills as well.

7. Wavelength and Frequency
For any kind of wave there exists a simple relationship between wavelength and frequency.
The wavelength is measured as the distance between two successive crests in a wave. The frequency is the number of wave crests that pass a a given point in space each second.

8. Understanding Waves
The traditional “slinky lab” as well as other activities to help understand waves.
An activity that allows students to experiment with waves-longitudinal and transverse.
Found in “Waves Light Up the Universe” Booklet

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

10. Umbrella Receiver Demo
Students discover a method of collecting radio frequencies by using an umbrella receiver.

11. 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)

12. 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

13. Herschel’s Experiment
Discovered Invisible Light
In 1800, Herschel places his control thermometer just outside the red end of the spectrum
Result: The outside thermometer registered the highest temperature

14. Conducting Herschel’s Experiment
Set up of Box Design for Conducting the Herschel Experiment.

15. Conducting Hershel’s Experiment
Place a sheet of white paper inside a cardboard box
Tape three thermometers together and place inside box
Cut a small notch in the top of the box and position a glass prism so that the spectrum is projected inside the box
Arrange the thermometers so that one is just outside the red end of the spectrum, with no visible light falling on it

16. 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

17. Roy G. Biv Activity
Students will discover and verify the relationship between the Wavelength and Frequency of the EMS.
Students compare the wavelength and frequencies of three colors of the visible light portion on the spectrum.

18. Red Sky – Blue Sky
A demonstration used to illustrate how the gases in the atmosphere scatter some wavelengths of visible light more than others.

19. 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)

20. 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

21. Chandra X-ray Observatory
Chandra is designed to observe X-rays from high energy regions of the universe, such as the remnants of exploded stars.
The most sophisticated observatory built to date.
Deployed by the Space Shuttle Columbia on July 23, 1999,
Chandra X-ray Observatory

22. 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

23. Sources of g-ray Emission
• Black holes
• Active Galaxies
• Pulsars
• Diffuse emission
• Supernovae
Gamma-ray bursts
• Unidentified

24. Source/Detector Activity
Students identify sources (emitters) and detectors of the various wavelengths of the EMS.
Students also have the opportunity to experiment with shields –or types of materials that prevent the transmission of wavelengths.

25. Exploring the EMS with NASA Missions
Radio
Infrared
Visible UV
X-ray
Gamma ray
Energy
(eV)
MAP
ASTRO-E2
Swift
SWAS
GLAST
GALEX
Chandra
RXTE
HETE-2
CHIPS
Con-X
INTEGRAL
XMM-Newton

27. And the universe for that matter!