Slide 1
Waves carry energy from one place to another
© 2000 Microsoft Clip Gallery
Slide 2
Waves (Def.) – A wave is a disturbance that transfers energy.
Medium – Substance or region through which a wave is transmitted.
Speed of Waves – Depends on the properties of the medium.
© 2000 Microsoft Clip Gallery
Slide 3
SAMPLE LESSON: Light & the Electromagnetic Spectrum
By D. L. Power
Revised 1/20/01
© 2000 Microsoft Clip Gallery
Slide 4
Albert Einstein
Slide 5
Light Energy
Atoms
As atoms absorb energy, electrons jump out to a higher energy level.
Electrons release light when falling down to the lower energy level.
Photons - bundles/packets of energy released when the electrons fall.
Light: Stream of Photons
© 2000 Microsoft Clip Gallery
© 2000 Microsoft Clip Gallery
Slide 6
Speed in Vacuum
300,000 km/sec
186,000 mi/sec
Speed in Other Materials
Slower in Air, Water, Glass
© 2000 Microsoft Clip Gallery
Slide 7
Energy is perpendicular to direction of motion
Moving photon creates electric & magnetic field
Light has BOTH Electric & Magnetic fields at right angles!
© 2000 Microsoft Clip Gallery
Slide 8
© 2000 Microsoft Clip Gallery
Slide 9
Electromagnetic Spectrum
Visible Spectrum – Light we can see
Roy G. Biv – Acronym for Red, Orange, Yellow, Green, Blue, Indigo, & Violet.
Largest to Smallest Wavelength.
Slide 10
Electromagnetic Spectrum
Invisible Spectrum
Radio Waves
Def. – Longest wavelength & lowest frequency.
Uses – Radio & T.V. broadcasting.
© 2000 Microsoft Clip Gallery
Slide 11
Modulation - variation of amplitude or frequency when waves are broadcast
AM – amplitude modulation