PPT-Waves I Physics 2415 Lecture 25

Michael Fowler UVa Todays Topics Dimensions Wave types transverse and longitudinal Wave velocity using dimensions Harmonic waves Dimensions There are three fundamental units in mechanics those of mass length and time . Doppler Effect. ~apparent change in frequency of a wave due to the motion of the source of the wave.. If the object is moving towards the observer the frequency will appear to increase. If the object is moving away from the observer the frequency will appear to decrease. Before the waves are made the particles are same distance apart. While waves moves through the medium the particles . compress. together, then they spread further apart (stretched areas)- . rarefaction.. Michael Fowler, . UVa. Today’s Topics. A bit more about mirrors…. Refraction. Lenses. Ray tracing to locate image. Concave Mirror Focusing Sunlight. This solar collector is really many small flat mirrors, but equivalent to a concave mirror focusing parallel rays to a point half way from the center of the mirror to its center of curvature.. Michael Fowler, . UVa. Today’s Topics. Huygens’ principle and refraction. Snell’s law and applications. Dispersion. Total internal reflection. Huygens’ Principle. Newton’s contemporary Christian Huygens believed light to be a wave, and pictured its propagation as follows: at any instant, the wave front has reached a certain line or curve. From every point on this wave front, a . Get 1 full page and 1 half page of paper. Fold full sheet of paper. about 1-1.5” short of even. Insert half sheet in the middle. Staple . across . the fold. Pick up the top two pages and starting from the bottom, cut the top two . Michael Fowler, UVa. Today’s Topics. Field lines and . equipotentials. Partial derivatives. Potential along a line from two charges. Electric breakdown of air. Potential Energies Just Add. Suppose you want to bring one charge . Michael Fowler, UVa. Today’s Topics. Continuous charge distributions: line of charge. Visualizing the field: lines of force. Electron moving in a field. Electric dipoles. Superposition. The . total electric force . Periodic Motion. Motion that repeats in a regular cycle is called . periodic motion. . . The revolution of a planet about its sun is an example of periodic motion. The highly reproducible period (T) of a planet is also called its year.. - Jon . Kabat. -Zinn. Waves are moving . energy. !. Most waves wind-driven. Moving energy along ocean/air interface:. Wind main disturbing force. Boundary between and within fluids with different densities. Michael Fowler, . UVa. Today’s Topics. Multi-slit interference. The diffraction grating: spectra. Waves and particles, more diffraction. Radio astronomy. Light Intensity Pattern from Two Slits. We have two equal-strength rays, phase shifted by. Earthquakes-Tsunamis. Graviational. attraction-Tides. Wind waves move energy, not matter. Wind waves- Growth. Wind strength- must be moving faster than waves. Wind duration-longer creates larger waves. Michael Fowler, . UVa. Today’s Topics. Electric motors and galvanometers. Ratio of charge to mass for an electron. Hall Effect. Mass spectometry. Reviewing Essential Facts:. The force on an element of current in a wire in a magnetic field is:. The Scottish physicist James Clerk Maxwell (1831–1879) was the first person to truly understand the fundamental nature of light. . He proved in 1865 that an electromagnetic disturbance should propagate in free space with a speed equal to that of light.. Interference I: Double Slit Physics 2415 Lecture 35 Michael Fowler, UVa Today’s Topics First: brief review of optical instruments Huygens’ principle and refraction Refraction in fiber optics and mirages Young’s double slit experiment Convex