1. Electromagnetic Spectrum
Use : spectra of periodic table of elements

2. 1. The Study of Light
The electromagnetic spectrum is the arrangement of electromagnetic radiation according to wavelength.
Electromagnetic radiation includes gamma rays, X-rays, ultraviolet light, visible light, infrared radiation, microwaves, and radio waves.

4. 2. Behavior of Light
In some instances light behaves like waves, and in others, like particles.
In the wave sense, light can be thought of as swells in the ocean. This motion is characterized by a property known as wavelength, which is the distance from one wave crest to the next.
Frequency is the number of wave crests that pass a given point in space each second.

5. Wavelength

6. A. Characteristics of waves
Amplitude = distance from the origin to the crest
Wavelength () = distance between adjacent crests
Frequency (υ) = number of waves per second

7. A. Characteristics of waves
All waves have a characteristic wavelength, l.
Wavelength is measured in nanometers (10-9 m) or meters.
The frequency, υ, of a wave is the number of cycles which pass a point in one second.
Unit of frequency is 1/s (s-1) or hertz (Hz)
Wavelength = lambda
Frequency = nu (upper case is N)

8. Characteristics of waves
The speed of a wave, c, is given by its wavelength multiplied by its frequency :
For all types of electromagnetic radiation, the speed in vacuum is c = 3.0  108 m/s (also known as the speed of light)

10. Size of waves
0.5 x 10-6
103
10-2
10-5
10-8
10-10
10-12

11. Draw what each type of wave looks like below
Makes no sense without caption in book

12. So, a wave with a long wavelength and low frequency = , and a short wavelength and high frequency =
The only difference between radio waves, visible light, and gamma-rays is the energy of the photons. Radio and TV waves have low energy, visible light has more energy and gamma waves have the highest energy.
TV and Radio waves
Gamma waves

13. Nasa 5 minute video summary

14. 3. Spectroscopy
Spectroscopy is the study of the properties of light that depend on wavelength.
Types of Spectrums a. Continuous Spectrum
• A continuous spectrum is an uninterrupted band of light emitted by an incandescent solid, liquid, or gas under pressure.
Incandescent = glowing b/c of heating

15. 3. Spectroscopy Types of Spectrums
Look at the overhead lights through the spectroscope and color the spectrum on your paper.
Incandescent = glowing b/c of heating

16. b. Absorption Spectrum
An absorption spectrum is a continuous spectrum produced when white light passes through a cool gas under low pressure. The gas absorbs selected wavelengths of light, and the spectrum looks like it has dark lines superimposed.

18. c. Emission Spectrum
An emission spectrum is a series of bright lines of particular wavelengths produced by a hot gas under low pressure.
1. When the spectrum of a star is studied, the spectral lines act as “fingerprints.” These lines identify the elements present and thus the star’s chemical composition.

19. Emission spectrum Hg Ca Na

20. Formation of Spectra
Makes no sense without caption in book

21. 4. The Doppler Effect
a. The Doppler effect is the apparent change in frequency of electromagnetic or sound waves caused by the relative motions of the source and the observer.
b. In astronomy, the Doppler effect is used to determine whether a star or other body in space is moving away or toward Earth.

22. Blue-shift
c. If an object is moving towards Earth, the waves are compressed, so their wavelength is shorter. The lines are shifted to shorter (bluer) wavelengths---this is called a blue-shift.
Makes no sense without caption in book

23. Red-shift
d. If the object is moving away from Earth, the waves are stretched out, so their wavelength is longer. The lines are shifted to longer (redder) wavelengths---this is called a red-shift.
Makes no sense without caption in book

24. The Doppler Effect Shorter Wavelength = blue shift
Longer Wavelength = red shift
Makes no sense without caption in book

25. Doppler effect – sound waves

26. https://www. youtube. com/watch

27. Absorption Spectrum of Our Sun

29. Add these notes to your TOC
At lab you will need:
lab sheet
Colored pencils
spectroscopes