Waves carry energy from one place to another WAVES: SOUND & LIGHT

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. NATURE OF WAVES

Amplitude: the height of the wave, measured in meters. Wavelength: the distance between adjacent crests, measured in meters. Period: the time it takes for one complete wave to pass a given point, measured in seconds. Frequency: the number of complete waves that pass a point in one second, measured in inverse seconds, or Hertz (Hz). is the number of occurrences of a repeating event per unit time. Speed: the horizontal speed of a point on a wave as it propagates, measured in meters / second. PROPERTIES OF WAVES

PROPERTIESOF LIGHT WAVE

-Reflection – Light is reflected off the surface like mirror such that angle of incidence is equal to angle of reflection. -Refraction – Bending of light due to a change in speed. Refraction is the bending of light as it passes between material of different optical density. -Interference - When two light waves coincide, it can create either constructive or destructive interference based on how crest & trough of each wave coincide with other. PROPERTIES OF LIGHT WAVE

-Dispersion - Light is composed of waves of different wavelengths that correspond to different colors of lights. When light wave passes through a material, these different wavelengths causes refraction by different amounts according to the wavelengths and which gives rise to different colors seen through prism or for rainbow. -Diffraction - This is the bending of light waves around obstacles in its path. ex. When a light wave comes against a barrier with a small opening, it acts as a single point source from where light emerges in all direction. PROPERTIES OF LIGHT WAVE

The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object. rangeelectromagnetic radiationrangeelectromagnetic radiation

Electromagnetic Spectrum

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

TYPES OF RADIATION IN THE EM SPECTRUM

-Invisible Spectrum -Radio Waves -Def. – Longest wavelength & lowest frequency. -Uses – Radio & T.V. broadcasting. Electromagnetic Spectrum

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

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

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

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

updated 11/22/97 updated 11/22/97 updated 2/1/97 updated 2/1/ or.html#links or.html#links rt.html rt.html ml#def ml#def WORKS CITED

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 LIGHT: What Is It?

All waves have certain properties. The three most important ones for audio work are shown here: Wavelength: The distance between any point on a wave and the equivalent point on the next phase. Literally, the length of the wave. Amplitude: The strength or power of a wave signal. The "height" of a wave when viewed as a graph. Higher amplitudes are interpreted as a higher volume, hence the name "amplifier" for a device which increases amplitude. Frequency: The number of times the wavelength occurs in one second. Measured in kilohertz (Khz), or cycles per second. The faster the sound source vibrates, the higher the frequency. Higher frequencies are interpreted as a higher pitch. For example, when you sing in a high-pitched voice you are forcing your vocal chords to vibrate quickly.

1. What is a disturbance that transfers energy? 2. What is the height of the wave, measured in meters? 3. What is the horizontal speed of a point on a wave as it propagates, measured in meters / second? 4. A Light is reflected off the surface like mirror such that angle of incidence is equal to angle of reflection? 5. A Bending of light due to a change in speed. Refraction is the bending of light as it passes between material of different optical density.

When two light waves coincide, it can create either constructive or destructive interference based on how crest & trough of each wave coincide with other. 6. When two light waves coincide, it can create either constructive or destructive interference based on how crest & trough of each wave coincide with other. 7. Light is composed of waves of different wavelengths that correspond to different colors of lights. is the range of all possible frequencies of electromagnetic radiation 8. is the range of all possible frequencies of electromagnetic radiation

Roy G. Biv 9. Roy G. Biv Illustrate the ff: (2 pts. each) ReflectionRefractionInterference