This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: October 31, 2008 PHY2054 Discussion-Fall 08 Quiz 7 (Chapter 19.7-20.8) Name: UFID: *1. (5pts) Four long, parallel wires carry equal currents of 2.00 A. The wires are directed perpendicular to the sheet and they pass the corners of a square with edge of length 0.500 m. The direction of the current is into the sheet for wire A and B and out of the sheet for wire C and D. Calculate the magnitude and direction of the magnetic field at point P, located at the center of the square. According to the 2 nd right hand rule, the magnetic fields due to the current A and D are directed to wire B, and the field due to the current B and C are directed toward D. Taking +x direction to the right and +y upward, we have B A = B D = (- I/(2r)cos45, - I/(2r)sin45) B B = B C = (+ I/(2r)cos45, - I/(2r)sin45) The net magnetic field is the sum of the field due to each current. Therefore B = B A +B B +B C +B D = (0, -4 I/(2r)sin45) = (0,-4410-72/(2(20.25 2 )) = (0, -3.2010)) = (0, -3....
View Full Document