I. Light and TimeII. Ripple Tank EffectIII. EM Property of LightIV. EM Waves in AstronomyV. SunlightI. Positive and Negatively Charged ParticlesII. TemperatureIII. Black Body RadiationIV. SpectroscopyI. Positive and Negatively Charged Particlesa. Every object we see is made up of positive and negative charged particlesb. Whenever you increase the T of an object, you are actually increasing the average thermal motion between those particlesc. Whenever charged particles oscillate (move rapidly) they emit electromagnetic radiationII. Temperaturea. Temperature: measure of how fast particles are moving in given material being analyzedb. Absolute scale gives more accurate characterization of thermal motion: kelvin scalei. At 0 K, all molecular motion ceases to happenIII. Black Body Radiationa. Ideal object that can absorb every light or energyb. As it absorbs it, it transforms the energy and thermalizes the energy, and emits it back into space in a particular fashionc. Stars are good representations of Black Bodiesd. Blackbody spectrum is determined ONLY by its TEMPERATUREi. Given a certain temperature, a curve (Planck curve) is given to show how much light is being emitted by that particular objecte. Radiation Laws:i. Wien’s Law: the higher the temperature, the more to the left the peak will be1. More ration of SHORTER wavelengths are being emitted (higher temperature, shorter wavelength)2. Lambda of max = .29mm/T (in K)ii. Stefan-Boltzmann Law: Tells how much energy is being emitted when increasing Temperature:1. Curve gets taller and taller as you increase the T2. The peak goes to the left (Wieins) AND the peak gets taller (Stefan-Boltz)3. F = sigma * T^4 (sigma – constant 5.67E-8 W.m^2 * K^4) F = energy per second per unit area4. Two stars with different surface areas and SAME Temp: stars with BIGGER SA will look BRIGHTERIV. Spectroscopya. Dark spots on the ribbon that shows the spectral emissions of the suni. If object is dense, colors not missing. If object is less dense, colors can be missingb. Kirchhoff’s Laws:i. First law: Hot dense objects emit a continuous spectrum1. Light is emitted when an electron jumps down an orbit (shell) and light is absorbed so that an electron can climb up to a higher energy level2. Bigger jumps have higher energy associated with the jumpsa. Blue light emitted for big jumps (UV or X ray emitted from even bigger jumps to higher energy levels)b. Red light emitted from a smaller jump (jumping to a lower energy level)c. Planck’s constant: 6.63E-34 joule seconds (J * s); light comes in packets of energy called photonsii. Second law: A hot transparent gas produces an emission light spectrum; a series of bright spectral lines against a dark background (emission spectra)1. Light passing through prism show colors that electrons like to emit; the colors you see are opposite of colors that are absorbediii. Third law: whenever you have dark lines (corresponding to colors missing) produces absorption spectra1. Absorption spectrum used to identify elements2. Sodium emits yellow light (i.e. flame test) so it absorbs all other colors besides the two nanometers of light that are missing)3. For absorption spectrum of the sun, the dark spots help us identify which elements are present on the suna. Light must pass through these elementsASTRON 89 1st Edition Lecture 9Outline of Last Lecture I. Light and Time II. Ripple Tank Effect III. EM Property of Light IV. EM Waves in Astronomy V. Sunlight Outline of Current Lecture I. Positive and Negatively Charged Particles II. Temperature III. Black Body Radiation IV. Spectroscopy Current LectureI. Positive and Negatively Charged Particles a. Every object we see is made up of positive and negative charged particlesb. Whenever you increase the T of an object, you are actually increasing the average thermal motion between those particles c. Whenever charged particles oscillate (move rapidly) they emit electromagnetic radiationII. Temperature a. Temperature: measure of how fast particles are moving in given material being analyzedb. Absolute scale gives more accurate characterization of thermal motion: kelvin scalei. At 0 K, all molecular motion ceases to happenIII. Black Body Radiation a. Ideal object that can absorb every light or energyb. As it absorbs it, it transforms the energy and thermalizes the energy, and emits it back into space in a particular fashionc. Stars are good representations of Black Bodiesd. Blackbody spectrum is determined ONLY by its TEMPERATUREi. Given a certain temperature, a curve (Planck curve) is given to show how much light is being emitted by that particular objectThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.e. Radiation Laws: i. Wien’s Law: the higher the temperature, the more to the left the peak will be1. More ration of SHORTER wavelengths are being emitted (higher temperature, shorter wavelength)2. Lambda of max = .29mm/T (in K)ii. Stefan-Boltzmann Law: Tells how much energy is being emitted when increasing Temperature:1. Curve gets taller and taller as you increase the T2. The peak goes to the left (Wieins) AND the peak gets taller (Stefan-Boltz)3. F = sigma * T^4 (sigma – constant 5.67E-8 W.m^2 * K^4) F = energy per second per unit area4. Two stars with different surface areas and SAME Temp: stars with BIGGER SA will look BRIGHTERIV. Spectroscopy a. Dark spots on the ribbon that shows the spectral emissions of the suni. If object is dense, colors not missing. If object is less dense, colors can be missingb. Kirchhoff’s Laws:i. First law: Hot dense objects emit a continuous spectrum1. Light is emitted when an electron jumps down an orbit (shell) and light is absorbed so that an electron can climb up to a higher energy level2. Bigger jumps have higher energy associated with the jumpsa. Blue light emitted for big jumps (UV or X ray emitted from even bigger jumps to higher energy levels)b. Red light emitted from a smaller jump (jumping to a lower energy level)c. Planck’s constant: 6.63E-34 joule seconds (J * s); light comes in packets of energy called photonsii. Second law: A hot transparent gas produces an emission light spectrum; aseries of bright spectral lines against a dark background (emission spectra)1. Light passing through prism show colors that electrons like to emit; the colors you see are opposite of colors that are absorbediii. Third law: whenever you