Wednesday, March 5, 2008

• Please give me feedback about this course on the mid-term evaluation form.
• You can earn extra credit by watching Al Gore's movie, An Inconvenient Truth and writing a short (~ 1 page) essay about what you learned from this film and insights that relate to this physics course.  This movie can be checked out from the MRC or Dr. Deardorff.

Assignments:

• Read Chapter 11 and be prepared to discuss on Friday.
• Answer the recommended conceptual exercises and problems for Chapter 10, and check your understanding by looking at the answers in the back of the textbook.
• Submit your topic ideas for the physics Web Project.
  

Chapter 9 - Electromagnetic Radiation

Spectroscopy - can you identify the elements?

Chapter 10 - Special Relativity

Special relativity deals with inertial frames of reference (a = 0) .  Simulation program: Warp
General relativity (a <> 0)
    Examples of inertial and non-inertial reference frames:  a) space ship traveling in a straight line, b) space shuttle in orbit, c) this classroom
Consequences of Special Relativity:  As v -> c, several physical parameters change by factor of gamma = 1/sqrt(1-v^2/c^2)
    Ponderable:  What are "relativistic" speeds?  (see table below)
Time dilates:  t = to*gamma
Length contracts:  L = Lo/gamma
Mass increases:  m = mo*gamma
Relativistic energy:  E = mc^2 = gamma*Eo
Relativistic KE:  K = Eo*gamma - Eo
General relativity: 
    All physical experiments yield identical results in an accelerated reference frame as they do in a gravitational field.
Black holes:  Light cannot escape a star with a radius less than or equal to the Schwarzschild radius:  R = 2GM/c^2

Step by Step into a Black Hole - Simulated views of a black hole.

Interactive Black Hole Simulation

Ponderable:  If an astronaut travels 1 ly at 0.9c, why is t <> to*gamma?