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1. [http://gtn.sonoma.edu/public/resources/presentations/06_03_02/img003.jpg][http://gtn.sonoma.edu/public/resources/presentations/06_03_02/img003.jpg]

2. Electromagnetic Waves • EM waves are created by vibrating electric charges. (electrons in atoms!) • These do not need a medium because they travel by transferring energy between electric and magnetic fields.

3. Electromagnetic Waves • These electric and magnetic fields continually create one another allowing for EM waves to exist. [http://www.monos.leidenuniv.nl/smo/basics/images/wave.gif] Click Here for a 3D EM Wave Demo

4. EM Wave Properties • The speed of an EM wave depends on the medium it is traveling through. • As the medium becomes more dense, the speed decreases! [http://micro.magnet.fsu.edu/primer/java/speedoflight/javalightspeedfigure1.jpg]

5. EM Wave Properties • In a vacuum, EM waves travel at 300,000,000 m/s. • Air is 299,997,000 m/s so we will use 300,000,000 m/s for simplicity.

7. Scientific Notation • Removes extra “zeros” from numbers to make them smaller. • Example: • 300,000,000. m/s • 3.0 x 108 m/s

8. Scientific Notation • Move decimal to the left = positive exponent. • 23,000,000. • Left 7 “spaces” • 2.3 x 107

9. Scientific Notation • Move decimal to the right = negative exponent. • 0.0000067 • Right 6 “spaces” • 6.7 x 10-6

10. Scientific Notation Calculations • Multiplication • Multiply the mantissas. • Add the exponents. • Mantissa must have only 1 number in front of the decimal.

11. Scientific Notation Calculations • Example: • (3.0 x 104) x (4.0 x 103) • 12.0 x 107 , but the mantissa is bigger than 10 so…. • 1.2 x 108

12. Scientific Notation Calculations • Division • Divide the mantissas. • Subtract the exponents. • Mantissa must have only 1 number in front of the decimal.

13. Scientific Notation Calculations • Example: • (2.0 x 107) / (4.0 x 103) • 0.5 x 104 , but the mantissa is less than 1 so… • 5.0 x 103

14. Scientific Notation & Calculators

15. Scientific Notation & Calculators • Graphing or 2-line (6.67 x 10-11) • Enter 6.67 • Press the EE Key • Enter -11 • 6.67 x 10-11

16. Scientific Notation & Calculators • One Line (3.71 x 10-5) • Enter 3.71 • Press the EE Key or EXP Key • Enter -5 • 3.71 x 10-5

17. Scientific Notation & Calculators • For both calculators, when entering negative exponents use the “negative” key not the “minus sign” key!!!