Preflight assignment 8


(Closed. Preflights are due at 10 AM on Tuesdays. )


Let's do a little review of complex numbers and simple harmonic motion. Don't look any of this stuff up, or get help - just do what you can, and let us know if there are questions that you can't do right now, but are sure you could do easily if you just spent a minute reviewing material you already know. Similarly, if a question looks quite unfamiliar, so it's not just a question of quick review, let us know that too!

(Although I say "don't get help", I would suggest you pull out a piece of paper for this one!)
  1. What is the magnitude of the complex number z=2-i? What is the complex conjugate of z=2-i?

  2. Express the complex number 2 e^(i pi/4) in the form "real part + i* imaginary part".

  3. Write the number (1-i)/(1+i) in the form A e^(i theta)


  4. In Phys 2170, when solving the ODE for a harmonic oscillator, you might have found a complex solution, Ae^(i omega t). That doesn't look real! Can you describe in words what the connection(s) was (were) between that very mathematically abstract result, and the old Phys 1110 "mass bobbing on a string" story?



  5. In Phys 2170, you might have talked about "resonance". Tell us, in your own words , what you remember about resonance (or, if you are not really familiar with this term, let us know) Be both as physical and as mathematical as you can.





  6. Please submit a question you have about the reading assigned for the upcoming class. What seemed hard, was something confusing, what would you like us to spend class time on? If you can't come up with any question, how about a comment - (did anything strike you as interesting? )
    Reminder: the reading assignments are on our course calendar

    Thanks for your time.