Differences

This shows you the differences between two versions of the page.

--- course_planning:184_projects:s18_project_15 [2018/04/24 16:03] – created dmcpadden
+++ course_planning:184_projects:s18_project_15 [2018/04/26 17:17] (current) – dmcpadden
@@ Line 21: / Line 21: @@
 Good Luck!
+===== And the winner is... =====
+==== Project 15B: Murder in the Mansion ====
+One stormy night...Colonel Mustard and Ms. Scarlet were having a dinner date in their ritzy mansion. All of a sudden, there was a scream: SOMEONE MURDERED THE MAID!! Currently, the prime suspects are the other four people that live in the mansion: Professor Plum, Mrs. White, Mr. Green, and Mrs. Peacock. It is up to you to check the validity of their alibis.
+__Mr. Green's Alibi:__ \\
+"I was trying to watch the season finale of The Bachelor, but the storm was messing with the satellite. I was on the roof trying to fix the satellite with my wrench, but I got struck with lightning and was passed out for a few hours on the roof."
+With some proper sleuthing and detective work, you know:
+  * Mr. Green's claimed location was  $\langle 0, 16, 0 \rangle$  m.
+  * The storm in question was comprised of three clouds:
+    *  $Q_1 = -500 C$ , location  $\langle 100, 2000, 0 \rangle$  m.
+    *  $Q_2 = -500 C$ , location  $\langle 0, 2000, 0 \rangle$  m.
+    *  $Q_3 = -500 C$ , location  $\langle -100, 2000, 0 \rangle$  m.
+  * It is plausible that Mr. Green was struck by lightning if the electric field is greater than 3 MV/m.
+__Mrs. Peacock's Alibi:__ \\
+"I was on my way home from the store on my electric scooter, but I got stranded a few miles away because the voltage on my battery was too low."
+You look up the circuit diagram of her scooter, which simplifies to the circuit below. In the manual, you learn that the battery must have a voltage of at least 20 V to work.
+{{ 184_notes:PeacockCircuit.png?300 }}
+__Professor Plum's Alibi:__
+"I was standing on the roof trying to get the perfect dramatic selfie with the storm as a background. When the lightning hit Mr. Green, my phone was thrown upward by the magnetic field, and it fell over the edge of the building. I spent the next couple of hours searching through the weeds to find my phone."
+Since this sounded a little sketchy, you drew up the following diagram, which shows the direction of current from the lightning bolt, Professor Plum's location, the current direction in the phone while selfie-taking, and the claimed trajectory of the phone. (Could the force on the phone from the lightning bolt make this trajectory?)
+{{  184_notes:roof.png?500 }}
+__Mrs. White's Alibi:__
+"I was on a walk when the storm hit, so I tried to call my husband to come pick me up. However, the electric potential from the storm caused problems my cell phone - it didn't work! It took me forever to walk home."
+After further questioning, Mrs. White claimed to have been 2000 m away (in the -x direction) from the mansion. You consult with the cell carrier who tell you that only electric potentials bigger than 5 GV would affect a cell signal.