## Fall 2000 Physics 272 Computer Exercises:

Notes for computer exercises : These are fun and easy exercises designed to help develop physical intuition .

To print out the results on a PC, hit the PrintScreen Key to save the plot from a JAVA applet. Then go to Word, Word Pad or Paint, and click Paste on the Edit Menu. You should then see the plot and be able to print by clicking Print from the File Menu. On UNIX, use a screen capture program. (If you have a problem printing out the result, it is acceptable to hand in a sketch drawn by hand.)
• Computer Exercise 1. Sketch some representative E field lines for the charge configuration given in problem 40 of Chapter 22 of the Text.
• Computer Exercise 2. Flip the switch to charge up the capacitor. Flip the switch to discharge the capacitor. Sketch the voltage across the capacitor as a function of time.
• Computer Exercise 3. Sketch the motion for two cases:
(a) when E and B are perpendicular (no initial velocity). Launch in the default configuration.
(b) for the case of no electric field (initial velocity in the x -z plane)
• Computer Exercise 4. Sketch the direction of the induced current for two cases:
(a) when tugging the coil to the left
(b) when tugging the coil to the right
Note that the induced current vanishes when you hold the coil fixed.
• Computer Exercise 5. Sketch the image and principal rays for
(I) a converging lens
(II) a diverging lens
(III) a diverging mirror
when the red arrow is placed (a) at the focal point (b) in front of the focal point (c) behind the focal point.

last revised 14 August 2000, jgl.