1. Electromagnetic Spectrum
Electrons in Atoms
Electromagnetic Spectrum

2. How does energy travel?
It travels through space as electromagnetic radiation
Electromagnetic Radiation
Is energy that exhibits wavelike behavior and travels through space at the speed of light in a vacuum.

3. Parts of a WAVE Crest Trough Crest – highest point of a wave
Trough – lowest point of a wave

4. How a WAVE travels
A wave travels through space according to three characteristics:
Wavelength
Frequency
Speed of Light

5. How a WAVE travels Wavelength- Represented by lambda (l)
Is the distance between two troughs or two crests

6. How a WAVE travels Frequency- Represented by f
Is the number of waves that pass a given point in one second
Units of Hertz (Hz) or s-1

7. How a WAVE travels
Speed of Light-
Represented by c

8. Wavelength and Frequency Relationship
Wavelength l
(Long or Small)
Frequency f
(fast or slow)
Trial A
Trial B
As l increases the f ___________________________
As l decreases the f __________________________

9. Types of Electromagnetic Radiation

10. Also known as the Continuous Spectrum
How can we remember the continuous spectrum?
R O Y G B I V

11. How do we see colors?
Electrons are excited and jump up to a higher energy level
When they are come back down to their ground state they emit the color we see

12. How does it prove the photoelectric effect?
Einstein said that electromagnetic radiation has both wavelike and particle like natures
It can behave as a wave or as a stream of tiny particles called photons
Photon –
No mass
Carries a quantum of energy
These photons carry enough energy to release an electron from an atom of a metal

13. Ephoton = hf Definition Where do we find it? Units Ephoton Energy
We calculate it
Joules (J) h
Planck’s Constant
On reference material
J • s f
frequency
s-1 or Hz

14. Practice with Ephoton = hf
A radio wave has a frequency of 3.80 x 1010 Hz. What is the energy of one photon of this radiation? Ephoton = h = f = Formula:

15. Practice with Ephoton = hf
In microwave radiation a photon has an energy of 8.34 x 10-24J. What is the frequency of this photon? Ephoton = h = f = Formula: