2000 Microsoft Clip Gallery WAVES 2000 Microsoft Clip

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© 2000 Microsoft Clip Gallery WAVES

© 2000 Microsoft Clip Gallery WAVES

© 2000 Microsoft Clip Gallery �Waves (Def. ) – A wave is a disturbance

© 2000 Microsoft Clip Gallery �Waves (Def. ) – A wave is a disturbance that transfers energy. �Waves carry energy from one place to another �Medium – Substance or region through which a wave is transmitted. �Speed of Waves – Depends on the properties of the medium.

Types of waves n n There are three types of waves: Mechanical waves require

Types of waves n n There are three types of waves: Mechanical waves require a material medium to travel (air, water, ropes). These waves are divided into three different types. n Transverse waves cause the medium to move perpendicular to the direction of the wave. n Longitudinal waves cause the medium to move parallel to the direction of the wave. n Surface waves are both transverse waves and longitudinal waves mixed in one medium.

Types of waves Electromagnetic waves do not require a medium to travel (light, radio).

Types of waves Electromagnetic waves do not require a medium to travel (light, radio). n Matter waves are produced by electrons and particles n

Types of Waves – Transverse n In a transverse wave, each element that is

Types of Waves – Transverse n In a transverse wave, each element that is disturbed moves in a direction perpendicular to the wave motion

Types of Waves – Longitudinal n n In a longitudinal wave, the elements of

Types of Waves – Longitudinal n n In a longitudinal wave, the elements of the medium undergo displacements parallel to the motion of the wave A longitudinal wave is also called a compression wave

Wave Terminology Height Still water line n • • Still water line – level

Wave Terminology Height Still water line n • • Still water line – level of ocean if it were flat w/o waves Crest – highest part of wave Trough – lowest part of wave Wave height (H) – vertical distance between crest and trough Amplitude – distance between crest and still water line – ½ the wave height • Wavelength (L) – horizontal distance from each crest or each trough – Or any point with the same successive point • Steepness = Height (H)/length (L)

LIGHT: What Is It? © 2000 Microsoft Clip Gallery Light Energy n Atoms n.

LIGHT: What Is It? © 2000 Microsoft Clip Gallery Light Energy n Atoms n. As atoms absorb energy, electrons jump out to a higher energy level. n. Electrons release light when falling down to the lower energy level. n Photons - bundles/packets of energy released when the electrons fall. n Light: Stream of Photons n © 2000 Microsoft Clip Gallery

Measuring waves n Any point on a transverse wave moves up and down in

Measuring waves n Any point on a transverse wave moves up and down in a repeating pattern. n The shortest time that a point takes to return to the initial position (one vibration) is called period, T. n The number of vibrations per second is called frequency and is measured in hertz (Hz). Here's the equation for frequency: f=1/T

Electromagnetic Waves n Speed in Vacuum n 300, 000 km/sec n 186, 000 mi/sec

Electromagnetic Waves n Speed in Vacuum n 300, 000 km/sec n 186, 000 mi/sec n Speed in Other Materials n Slower in Air, Water, Glass © 2000 Microsoft Clip Gallery

Transverse Waves © 2000 Microsoft Clip Gallery n Energy is perpendicular to direction of

Transverse Waves © 2000 Microsoft Clip Gallery n Energy is perpendicular to direction of motion n Moving photon creates electric & magnetic field n Light has BOTH Electric & Magnetic fields at right angles!

Electromagnetic Spectrum © 2000 Microsoft Clip Gallery

Electromagnetic Spectrum © 2000 Microsoft Clip Gallery

Electromagnetic Spectrum n Visible Spectrum – Light we can see n Roy G. Biv

Electromagnetic Spectrum n Visible Spectrum – Light we can see n Roy G. Biv – Acronym for Red, Orange, Yellow, Green, Blue, Indigo, & Violet. n Largest to Smallest Wavelength.

B. Waves of the Electromagnetic Spectrum n n Electromagnetic Spectrum—name for the range of

B. Waves of the Electromagnetic Spectrum n n Electromagnetic Spectrum—name for the range of electromagnetic waves when placed in order of increasing frequency Click here (Animation—Size RADIO WAVES INFRARED RAYS MICROWAVES of EMwaves) ULTRAVIOLET RAYS VISIBLE LIGHT GAMMA RAYS X-RAYS

Electromagnetic Spectrum n Invisible Spectrum n Radio Waves n. Def. – Longest wavelength &

Electromagnetic Spectrum n Invisible Spectrum n Radio Waves n. Def. – Longest wavelength & lowest frequency. n. Uses – Radio & T. V. broadcasting. © 2000 Microsoft Clip Gallery

Modulating Radio Waves © 2000 Microsoft Clip Gallery n Modulation - variation of amplitude

Modulating Radio Waves © 2000 Microsoft Clip Gallery n Modulation - variation of amplitude or frequency when waves are broadcast n AM – amplitude modulation n Carries audio for T. V. Broadcasts n. Longer wavelength so can bend around hills n FM – frequency modulation n. Carries video for T. V. Broadcasts

Short Wavelength Microwave n Invisible Spectrum (Cont. ) n Infrared Rays n. Def –

Short Wavelength Microwave n Invisible Spectrum (Cont. ) n Infrared Rays n. Def – Light rays with longer wavelength than red light. n. Uses: Cooking, Medicine, T. V. remote controls

Electromagnetic Spectrum n Invisible spectrum (cont. ). n Ultraviolet rays. n. Def. – EM

Electromagnetic Spectrum n Invisible spectrum (cont. ). n Ultraviolet rays. n. Def. – EM waves with frequencies slightly higher than visible light n. Uses: food processing & hospitals to kill germs’ cells n. Helps your body use vitamin D.

Electromagnetic Spectrum n Invisible Spectrum (Cont. ) n X-Rays n Def. - EM waves

Electromagnetic Spectrum n Invisible Spectrum (Cont. ) n X-Rays n Def. - EM waves that are shorter than UV rays. n Uses: Medicine – Bones absorb xrays; soft tissue does not. n Lead absorbs X-rays.

Electromagnetic Spectrum n Invisible spectrum (cont. ) n Gamma rays n. Def. Highest frequency

Electromagnetic Spectrum n Invisible spectrum (cont. ) n Gamma rays n. Def. Highest frequency EM waves; Shortest wavelength. They come from outer space. n. Uses: cancer treatment.

LIGHT: Particles or Waves? n Wave Model of Light n Explains most properties of

LIGHT: Particles or Waves? n Wave Model of Light n Explains most properties of light n Particle Theory of Light n Photoelectric Effect – Photons of light produce free electrons © 2000 Microsoft Clip Gallery

LIGHT: Refraction of Light n Refraction – Bending of light due to a change

LIGHT: Refraction of Light n Refraction – Bending of light due to a change in speed. n Index of Refraction – Amount by which a material refracts light. n Prisms – Glass that bends light. Different frequencies are bent different amounts & light is broken out into different colors.

Refraction (Cont. )

Refraction (Cont. )

Refraction-Spectroscope Lab Hey girls! The filters go on the Spectroscope, not on the lashes!

Refraction-Spectroscope Lab Hey girls! The filters go on the Spectroscope, not on the lashes! © 2000 D. L. Power

Color of Light Transparent Objects: n Light transmitted because of no scattering n Color

Color of Light Transparent Objects: n Light transmitted because of no scattering n Color transmitted is color you see. All other colors are absorbed. n Translucent: n Light is scattered and transmitted some. n Opaque: n Light is either reflected or absorbed. n Color of opaque objects is color it reflects. n © 2000 Microsoft Clip Gallery

Color of Light (Cont. ) n Color of Objects n White light is the

Color of Light (Cont. ) n Color of Objects n White light is the presence of ALL the colors of the visible spectrum. n Black objects absorb ALL the colors and no light is reflected back. © 2000 Microsoft Clip Gallery

Color of Light (Cont. ) © 2000 Microsoft Clip Gallery Primary Colors of Light

Color of Light (Cont. ) © 2000 Microsoft Clip Gallery Primary Colors of Light n Three colors that can be mixed to produce any other colored light n Red + blue + green = white light n Complimentary Colors of Light n Two complimentary colors combine to make white light-Magenta, Cyan, Yellow n

How You See © 2000 Microsoft Clip Gallery Retina – n Lens refracts light

How You See © 2000 Microsoft Clip Gallery Retina – n Lens refracts light to converge on the retina. Nerves transmit the image n Rods – n Nerve cells in the retina. Very sensitive to light & dark n Cones – n Nerve cells help to see light/color n

Paint Pigments © 2000 Microsoft Clip Gallery n Pigments absorb the frequency of light

Paint Pigments © 2000 Microsoft Clip Gallery n Pigments absorb the frequency of light that you see n Primary pigments n. Yellow + cyan + magenta = black n. Primary pigments are compliments of the primary colors of light.

Complementary Pigments © 2000 Microsoft Clip Gallery n Green, blue, red n Complimentary pigments

Complementary Pigments © 2000 Microsoft Clip Gallery n Green, blue, red n Complimentary pigments are primary colors for light! © 2000 Microsoft Clip Gallery

LIGHT & ITS USES © 2000 Microsoft Clip Gallery n Sources of Light n

LIGHT & ITS USES © 2000 Microsoft Clip Gallery n Sources of Light n Incandescent light – light produced by heating an object until it glows. © 2000 Microsoft Clip Gallery

LIGHT & ITS USES © 2000 Microsoft Clip Gallery n Fluorescent Light – n

LIGHT & ITS USES © 2000 Microsoft Clip Gallery n Fluorescent Light – n Light produced by electron bombardment of gas molecules n Phosphors absorb photons that are created when mercury gas gets zapped with electrons. The phosphors glow & produce light.

LIGHT & ITS USES - Neon n Neon light – neon inside glass tubes

LIGHT & ITS USES - Neon n Neon light – neon inside glass tubes makes red light. Other gases make other colors. © 2000 Microsoft Clip Gallery

LIGHT & ITS USES - Reflection n Reflection – Bouncing back of light waves

LIGHT & ITS USES - Reflection n Reflection – Bouncing back of light waves n Regular reflection – mirrors smooth surfaces scatter light very little. Images are clear & exact. n Diffuse reflection – reflected light is scattered due to an irregular surface.

LIGHT & ITS USES: Reflection Vocabulary n Enlarged – n Image is larger than

LIGHT & ITS USES: Reflection Vocabulary n Enlarged – n Image is larger than actual object. n Reduced – n Image is smaller than object. © 2000 Microsoft Clip Gallery

LIGHT & ITS USES: Reflection Vocabulary © 2000 Microsoft Clip Gallery n Erect –

LIGHT & ITS USES: Reflection Vocabulary © 2000 Microsoft Clip Gallery n Erect – n Image is right side up. n Inverted – n Image is upside down. © 2000 Microsoft Clip Gallery

LIGHT & ITS USES: Reflection Vocabulary n Real Image – n Image is made

LIGHT & ITS USES: Reflection Vocabulary n Real Image – n Image is made from “real” light rays that converge at a real focal point so the image is REAL n Can be projected onto a screen because light actually passes through the point where the image appears n Always inverted

LIGHT & ITS USES: Reflection Vocabulary n Virtual Image– n “Not Real” because it

LIGHT & ITS USES: Reflection Vocabulary n Virtual Image– n “Not Real” because it cannot be projected n Image only seems to be there!

Light & Its Uses: Mirrors n Reflection Vocabulary n Optical Axis – Base line

Light & Its Uses: Mirrors n Reflection Vocabulary n Optical Axis – Base line through the center of a mirror or lens n Focal Point – Point where reflected or refracted rays meet & image is formed n Focal Length – Distance between center of mirror/lens and focal point © 2000 Microsoft Clip Gallery

LIGHT & ITS USES: Mirrors n Plane Mirrors – Perfectly flat n Virtual –

LIGHT & ITS USES: Mirrors n Plane Mirrors – Perfectly flat n Virtual – Image is “Not Real” because it cannot be projected n Erect – Image is right side up © 2000 Microsoft Clip Gallery

LIGHT & ITS USES: Mirrors n Reflection & Mirrors (Cont. ) n Convex Mirror

LIGHT & ITS USES: Mirrors n Reflection & Mirrors (Cont. ) n Convex Mirror n. Curves outward n. Enlarges images. n Use: Rear view mirrors, store security… CAUTION! Objects are closer than they appear! © 2000 Microsoft Clip Gallery

LIGHT & ITS USES: Lenses n Convex Lenses n Thicker in the center than

LIGHT & ITS USES: Lenses n Convex Lenses n Thicker in the center than edges. n Lens that converges (brings together) light rays. n Forms real images and virtual images depending on position of the object

LIGHT & ITS USES: Lenses n Convex Object Focal Point Lenses Lens n Ray

LIGHT & ITS USES: Lenses n Convex Object Focal Point Lenses Lens n Ray Tracing n Two rays usually define an image n. Ray #1: Light ray comes from top of object; travels parallel to optic axis; bends thru focal point. © 2000 D. L. Power

LIGHT & ITS USES: Lenses Ray #1 n Convex Lenses n Ray Tracing Ray

LIGHT & ITS USES: Lenses Ray #1 n Convex Lenses n Ray Tracing Ray #2 n Two rays define an image n. Ray 2: Light ray comes from top of object & travels through center of lens. © 2000 D. L. Power

LIGHT & ITS USES: Lenses © 2000 D. L. Power n Concave Lenses –

LIGHT & ITS USES: Lenses © 2000 D. L. Power n Concave Lenses – n Lens that is thicker at the edges and thinner in the center. n Diverges light rays n All images are erect and reduced.

How You See Near Sighted – Eyeball is too long and image focuses in

How You See Near Sighted – Eyeball is too long and image focuses in front of the retina n Far Sighted – Eyeball is too short so image is focused behind the retina. n © 2000 Microsoft Clip Gallery

LIGHT & USES: Lenses n Concave Lenses – n Vision – Eye is a

LIGHT & USES: Lenses n Concave Lenses – n Vision – Eye is a convex lens. n. Nearsightedness – Concave lenses expand focal lengths n. Farsightedness – Convex lenses shortens the focal length.

LIGHT & USES: Optical Instruments n Cameras n Telescopes n Microscopes © 2000 Microsoft

LIGHT & USES: Optical Instruments n Cameras n Telescopes n Microscopes © 2000 Microsoft Clip Gallery

LIGHT & USES: Optical Instruments n LASERS n Acronym: Light Amplification by Stimulated Emission

LIGHT & USES: Optical Instruments n LASERS n Acronym: Light Amplification by Stimulated Emission of Radiation n Coherent Light – Waves are in phase so it is VERY powerful & VERY intense.

LIGHT & USES: Optical Instruments n LASERS n Holography – Use of Lasers to

LIGHT & USES: Optical Instruments n LASERS n Holography – Use of Lasers to create 3 -D images n Fiber Optics – Light energy transferred through long, flexible fibers of glass/plastic n Uses – Communications, medicine, t. v. transmission, data processing.

LIGHT & USES: Diffraction – Bending of waves around the edge of a barrier.

LIGHT & USES: Diffraction – Bending of waves around the edge of a barrier. New waves are formed from the original. breaks images into bands of light & dark and colors. n Refraction – Bending of waves due to a change in speed through an object. n

LIGHT & USES: Diffraction © 2000 Microsoft Encarta n A diffraction grating. Each space

LIGHT & USES: Diffraction © 2000 Microsoft Encarta n A diffraction grating. Each space between the ruled grooves acts as a slit. The light bends around the edges and gets refracted.

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 1) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 1) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 3)

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 3)

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 3) Hey girls, © 2000 D. L.

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 3) Hey girls, © 2000 D. L. Power are you hard at work or hardly working?

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 5) Note: There’s more posing than working!

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 5) Note: There’s more posing than working! © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 5) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 5) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 5) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 5) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 6) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 6) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 6) © 2000 D. L. Power

SAMPLE STUDENT PROJECT: Diffraction Grating Glasses (Pd. 6) © 2000 D. L. Power

EVALUATION: State Standards Waves carry energy from one place to another n Identify transverse

EVALUATION: State Standards Waves carry energy from one place to another n Identify transverse and longitudinal waves in mechanical media such as spring, ropes, and the earth (seismic waves) n Solve problems involving wavelength, frequency, & speed. . n

EVALUATION: State Standards Radio waves, light, and x-rays are different wavelength bands in the

EVALUATION: State Standards Radio waves, light, and x-rays are different wavelength bands in the spectrum of electromagnetic waves whose speed in vacuum is approximately 3 x 10 m/sec n Sound is a longitudinal wave whose speed depends on the properties of the medium in which it propagates. n

EVALUATION: State Standards n Identify the characteristic properties of waves: n Interference n Diffraction

EVALUATION: State Standards n Identify the characteristic properties of waves: n Interference n Diffraction n Refraction n Doppler Effect n Polarization.

References http: //www. scimedia. com/chem-ed/light/em-spec. htm, updated 2/1/97 http: //encarta. msn. com/find/Concise. asp? ti=06

References http: //www. scimedia. com/chem-ed/light/em-spec. htm, updated 2/1/97 http: //encarta. msn. com/find/Concise. asp? ti=06 AFC 000 http: //www. lbl. gov/Micro. Worlds/ALSTool/EMSpec 2. html http: //www. lbl. gov/Micro. Worlds/ALSTool/EMSpec. html http: //www. physics. sfasu. edu/astro/color. html#linkshttp: //www. physics. sfasu. edu/ast ro/color. html#links http: //www. isc. tamu. edu/~astro/color. html

References http: //www. isc. tamu. edu/~astro/color. html http: //www. holo. com/holo/cmpany/laserart. htmlhttp: //www. holo.

References http: //www. isc. tamu. edu/~astro/color. html http: //www. holo. com/holo/cmpany/laserart. htmlhttp: //www. holo. com /holo/cmpany/laserart. html http: //www. holo. com/holo/book 1. html#defhttp: //www. holo. co m/holo/book 1. html#def http: //www. scimedia. com/chem-ed/light/em-rad. htm, updated 11/22/97

WORKS CITED n http: //www. scimedia. com/chem-ed/light/em-rad. htm, updated 11/22/97 n http: //www. scimedia.

WORKS CITED n http: //www. scimedia. com/chem-ed/light/em-rad. htm, updated 11/22/97 n http: //www. scimedia. com/chem-ed/light/em-spec. htm, updated 2/1/97 n http: //encarta. msn. com/find/Concise. asp? ti=06 AFC 000 n n http: //www. lbl. gov/Micro. Worlds/ALSTool/EMSpec 2. html n n http: //www. lbl. gov/Micro. Worlds/ALSTool/EMSpec. html n n http: //www. physics. sfasu. edu/astro/color. html#links n n http: //www. isc. tamu. edu/~astro/color. html n n http: //www. holo. com/holo/cmpany/laserart. html n n n http: //www. holo. com/holo/book/book 1. html#def

The End… © 2000 Microsoft Clip Gallery

The End… © 2000 Microsoft Clip Gallery