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

Electromagnetic WavesElectromagnetic 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.

Electromagnetic WavesElectromagnetic Waves These electric

and magnetic fields continually create one another allowing for EM waves to exist.

Click Here for a 3D EM Wave Demo

[http://www.monos.leidenuniv.nl/smo/basics/images/wave.gif]

EM Wave PropertiesEM 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]

EM Wave PropertiesEM 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.

Scientific NotationScientific Notation

Removes extra “zeros” from numbers to make them smaller.

Example: 300,000,000. m/s 3.0 x 108 m/s

Scientific NotationScientific Notation

Move decimal to the left = positive exponent.

23,000,000. Left 7 “spaces” 2.3 x 107

Scientific NotationScientific Notation

Move decimal to the right = negative exponent.

0.0000067 Right 6 “spaces” 6.7 x 10-6

Scientific Notation CalculationsScientific Notation Calculations

Multiplication Multiply the mantissas. Add the exponents. Mantissa must have only 1

number in front of the decimal.

Scientific Notation CalculationsScientific 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

Scientific Notation CalculationsScientific Notation Calculations

Division Divide the mantissas. Subtract the exponents. Mantissa must have only 1

number in front of the decimal.

Scientific Notation CalculationsScientific 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

Scientific Notation & CalculatorsScientific 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

Scientific Notation & Scientific Notation & CalculatorsCalculators

One Line (3.71 x 10-5)Enter 3.71Press the EE Key or EXP Key

Enter -5

3.71 x 10-5

Scientific Notation & CalculatorsScientific Notation & Calculators

Scientific Notation & CalculatorsScientific Notation & Calculators

For both calculators, when entering negative exponents use the “negative” key not the “minus sign” key!!!