electromagnetic radiation radiant energy that exhibits wavelength- like behavior and travels through...

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Electromagnetic Radiation Radiant energy that exhibits wavelength-like behavior and travels through space at the speed of light in a vacuum. Example: The sun light, energy used in microwave oven, the x- rays used by doctors.

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Page 1: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Electromagnetic Radiation

Radiant energy that exhibits wavelength-like behavior and travels through space at the speed of light in a vacuum.

Example: The sun light, energy used in microwave oven, the x-rays used by doctors.

Page 2: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Classification of Electromagnetic Radiation

Page 3: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

The Nature of Waves

Page 4: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

A Continuous Spectrum (a) and A Hydrogen Line Spectrum (b)

For the Hydrogen Spectrum:A Change between Two

Discrete Energy Levels—More Distance=More energy

(a)

(b)

Page 5: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Electrical energy is absorbed and excites the electrons to higher energy levels. The electrons then emit (give off) energy in the form of visible light.

Electricity or heat in visible light out

Page 6: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Energy

Ultra VioletLyman

InfraredPaschen

VisibleBalmer

65

3

2

1

4

n

Page 7: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Neon lights Fireworks displays Flame test and spectrum tubes

Page 8: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Ultraviolet (UV) energy is absorbed and excites the electrons to higher energy levels. The electrons then emit (give off) energy in the form of visible light.

UV light in visible light out

Page 9: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Black light posters Neon colored posters, product packages Laundry brighteners/whiteners Fluorescent dyes & inks Certain minerals/rocks

Page 10: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Visible and/or Ultraviolet (UV) energy is absorbed and excites the electrons to higher energy levels. The electrons then emit (give off) energy in the form of visible light with a time delay.

visible or UV light in time delay visible light out

Page 11: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

http://web.uvic.ca/ail/techniques/Jablonski.jpg

Page 12: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Glow in the dark stuff Zinc sulfide—older glow-

in-the-dark material—doesn’t last as long

Strontium aluminate—newer glow-in-the-dark material—lasts much longer

http://cdn2.ioffer.com/img/item/128/809/943/gJBaVSbiNnEwYRe.jpg

Page 13: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Chemicals are mixed and the energy excites electrons. Instead of energy being released in the form of heat, the energy is released in the form of “cool” light. This is chemiluminesence.

If this occurs in a living organism it is called bioluminescence.

chemical energy in visible light out

Page 14: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

http://whyfiles.org/shorties/081firefly/images/turpin_fireflies.jpg

http://courses.cm.utexas.edu/archive/Fall2001/CH210C/Syllabi/118k/118K%20Supplements_files/temp.h5.gif

Page 15: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Light sticks Fireflies Many deep sea

organisms

http://www.mbari.org/itd/images/retrospective/colobonema.jpg

http://static.howstuffworks.com/gif/light-stick-2.jpg

Page 16: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Mechanical energy excites the electrons in adhesive molecules, which then excite the electrons around nitrogen atoms in the air. The energy is then emitted in the form of visible light. (Magic tape example)

In the case of wintergreen, the methyl salicylate molecules are fluorescent, and so the mechanical energy excites the electrons in the wintergreen flavoring.

mechanical energy in visible light out

Page 17: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Bandage packages/Scotch® tape Crushing wintergreen candies

http://www.geocities.com/rainforest/9911/tribo.htm

Page 18: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

The light produced is of a single phase and is combined to produce a coherent beam of light laser light.

electrical energy in coherent light emitted

Page 19: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Electrical energy is used to stimulate the electrons, and visible coherent light of a single phase is emitted.

Page 20: Electromagnetic Radiation Radiant energy that exhibits wavelength- like behavior and travels through space at the speed of light in a vacuum.  Example:

Grocery store scanners Levels used in building Laser surgery

http://static.howstuffworks.com/gif/laser-level-2.jpg

http://medicineworld.org/images/blogs/12-2007/lasik-surgery-16190.jpg