1. Spectroscopy Is the science of studying the properties of light
Visible light was in fact a mixture of different kinds of light
Spectroscopy

2. Electromagnetic Waves
Electromagnetic radiation that transfer energy as they travel through space.
Travel at the speed of light (eight laps around Earth in one second)
Nothing travels faster than the speed of light in a vacuum.
“speed limit” for the universe.
Electromagnetic Waves

3. Electromagnetic Spectrum
Name for the range of electromagnetic waves when placed in order of increasing frequency

4. Wavelength
Frequency
The distance between successive crests (tops) of a wave
How often a wave repeats in an amount of time
Short wavelength
High frequency
Long wavelength
Low frequency

5. Notice the wavelength is
long (Radio waves) and gets shorter (Gamma Rays)
CFU!
In the Visible light section,
Which color has a long wavelength?

6. GAMMA RAYS Shorter wavelength and higher frequency than X-rays
Carry the greatest amount of energy and penetrate the most.

7. The Incredible Hulk was the victim of gamma radiation.
(Don’t try this at home: you wont gain superpowers)
Used in radiation treatment to kill cancer cells. x
Can be very harmful if not used correctly.

8. Exploding nuclear weapons emit gamma rays.
What do you think would happen if a nuclear weapon would explode over a major city?
Exploding nuclear weapons emit gamma rays.

9. X- RAYS
longer wavelength and lower frequency than Gamma rays
Carry a great amount of energy
Can penetrate most matter.

10. Bones and teeth absorb x-rays
Bones and teeth absorb x-rays. (The light part of an x-ray image indicates a place where the x-ray was absorbed)
X-rays from when a patient broke their collar bone and had a titanium rod installed.

11. Why do they put that lead vest on us?
Too much exposure can cause cancer
(lead vest at dentist protects organs from unnecessary exposure)

12. longer wavelength and lower frequency than X-rays
ULTRAVIOLET (UV) RAYS
longer wavelength and lower frequency than X-rays
Carry more energy than visible light

13. Other Uses of UV Rays UV rays are used to activate chemicals.
(teeth whitening & nail curing)
UV rays are used to kill bacteria. (Sterilization of equipment)

14. Too much can cause skin cancer.
Use sun block to protect against (UV rays)
CFU! So far, which energy sources are cancer causing?
UV rays also causes your skin to produce vitamin D (good for teeth and bones)

15. VISIBLE LIGHT WHICH COLOR HAS MORE ENERGY: RED OR BLUE?
GREEN OR YELLOW?
longer wavelength and lower frequency than UV rays.
Electromagnetic waves we can see.
Longest wavelength= red light
Less energy
Shortest wavelength= violet (purple) light
More energy
ROY G BIV

16. INFRARED RAYS
Infrared= below red VISIBLE LIGHT
LONGER wavelength and LOWER frequency than Visible light.

17. HEAT ENERGY!!!
People and animals give off infrared rays.
Objects such as heat lamps give off infrared waves.
Thermogram—a picture that shows regions of different temperatures in the body. Temperatures are calculated by the amount of infrared radiation given off.

18. MICROWAVES
Have the longer wavelengths and the lower frequency than infrared waves.

19. Used in microwave ovens.
-Waves transfer energy to the water in the food causing them to vibrate which in turn transfers energy in the form of heat to the food.
Also satellites

20. RADIO WAVES
Have the longest wavelengths and lowest frequencies of all the electromagnetic waves.
Lowest energy

21. RADAR (Radio Detection and Ranging)
Global Positioning Systems (GPS) measure the time it takes a radio wave to travel from several satellites to the receiver, determining the distance to each satellite.
RADAR (Radio Detection and Ranging)
Used to find the speed of an object by sending out radio waves and measuring the time it takes them to return.

22. A radio picks up radio waves through an antenna and converts it to sound waves.
Each radio station in an area broadcasts at a different frequency.
# on radio dial tells frequency.