PHY 111, Fall, 2005

Week 6

 

  Main Objectives
bulletYou should be able to explain how Kepler's third law can be derived from the law of gravity.  (in words, not math)
bulletYou should be able to define the following terms:
bulletkinetic energy
bulletpotential energy
bulletescape veloctiy
bulletwave
bulletfrequency
bulletwavelength
bulletblackbody
bulletthermal radiation
bulletatom
bulletelement
bulletnucleus
bulletelectron
bulletion
bulletYou should know:
bulletthe relationship between frequency, wavelength and wave speed
bullethow the total amount of radiation emitted by a blackbody depends on its temperature and its area
bulletwhat the graph of energy versus wavelength looks like for a blackbody
bullethow the peak of that graph changes with the temperature of the blackbody
bulletthe numerical value of the speed of light in a vacuum
bulletwhether a red star or a blue star is hotter and be able to explain why
bulletwhy our eyes observe color only for very bright stars
bulletwhy a red object looks red
bullethow the temperature of an object is related to the motion of its molecules
bulletYou should be able to name several kinds of electromagnetic waves and list them in order of highest to lowest wavelength
bulletYou should be able to explain why we divide electromagnetic waves into groups according to wavelength and what property all electromagnetic waves have in common
Tuesday Complete discussion of Newton's law of gravity.  Discuss how Kepler's laws may be derived from Newton's laws.  Go over exam. 

Outside of class: Read Chapter 4 Sec. 1-4.  Look over the multiple choice questions on your exam and be prepared to ask questions on Thursday about any you don't understand. Complete the study habits questionaire to be turned in on Thursday.
Thursday Introduction to energy concepts.  Introduction to waves.  Discussion of different kinds of electromagnetic waves. Discuss two models of the emission and absorption of light: blackbodies and spectra

Outside of class: Read Chapter 4 Sec. 5-8. Read handout on energy concepts.  Complete Ch. 4 Questions to Ponder 8, 12, and 13 and Calculations 1, 6, and 12 to be turned in on Tuesday.