Types of Waves
Waves Water waves Light waves Sound waves Seismic waves
Wave nature of light Amplitude- The height of the wave.
Wave characteristics of light Frequency and wavelength are inversely related c = λν Or V=fλ c or V= 3.0 x 108 m/s λ= wavelength (m) v or f= frequency (Hertz= Hz)
Types of Waves Longitudinal Wave (Compression)- Vibrates parallel (in the same direction) to the wave traveling. Ex: Sound Waves Particles bump into each other Compression- Particles get closer together. Rarefaction- Particles becoming thinner or more spread out. The opposite of compressions.
Period- The time it takes for 1 full wave to pass. Transverse- Vibrate perpendicular (at right angles) to the wave traveling. Particles move up and down while wave moves left to right. Period- The time it takes for 1 full wave to pass. Period= 1 / Frequency Units: Seconds / Wave
Properties of Waves 1) Reflection: Hitting a barrier. RADAR- Send out EM waves and they bounce back. 2) Refraction: Bending a wave when the medium through which it travels changes. Submarines use refraction in order not to be detected.
3) Diffraction- Spreading of waves Bending waves around obstacles and openings. Owls use this to communicate over long distances 4) Interference- Reinforcement or canceling of waves. Constructive Destructive
Doppler Effect http://science.discovery.com/videos/time-doppler-effect.html An apparent shift in frequency for a sound wave produced by a moving source. Shift in frequency + wavelength of waves which results from a source moving with respect to the medium. Works for all types of waves including light. Red shift - Occurs when the source + observer are moving away from each other. Blue shift- Occurs when the source + observer are moving towards each other.
Electromagnetic Spectrum
Visible Light Red – Longest wave, lowest energy Orange Yellow Green Blue Indigo Violet – Shortest Wave, highest energy
Line Spectrum
Seeing Color Retina- Made up of two types of cells that absorb light. Cones- Distinguish colors and detailed shapes; most effective in daytime vision. Rods- Sensitive to dim light; most effective in nighttime vision. Color Blindness- Results when one or more sets of cones do not function properly.