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Image 5 : A geometric figure indicates the puzzle pageThis Week's Puzzle

This assignment is due before 10 AM, Friday, April 6th, 2012.

  • Puzzle solutions are due by 10:00 AM on Friday of each week.
  • Puzzles are worth 5 points of extra credit each.
  • Answers must be accompanied by valid reasoning. Just like the tests, the answer alone isn't enough!
  • Each week, the first student to submit a correct answer will receive the stylish 25100 T-shirt.
  • Previous winners get a "virtual t-shirt." No shirt, but a chance to win a prize with actual value at the end of the semester (often a book, or maybe software).
  • Please enter your solution in the text area at the bottom of this page. DON'T FORGET TO GIVE YOUR NAME!
"Play Bulb!"

Battery circuit diagram

The circuit above shows a battery, two identical lightbulbs, an inductor and a switch. All of the components may be considered to be ideal. Initially, no currents are flowing. At t = 0, the switch is closed, it is left closed for a long time, then it is reopened, and another long time passes.

Just after the switch is first closed, which bulb will be brighter? What about just before it is reopened? Just after it is reopened? Finally, which bulb will emit more total light during the course of the experiment?

Please write your answer in the box below. Give an explanation of the reasoning behind your answer.

You may change your mind as often as you wish.
When you are satisfied with your responses, click the SUBMIT button.

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©2012 A. Gavrin, all rights reserved.