1. The problem statement, all variables and given/known data A long straight wire carries a current 36 A. A rectangular loop with two sides parallel to the straight wire has sides 7.5 cm and 15 cm with its near side a distance 3 cm from the straight wire as shown in the figure. The permeability of free space is 4π e -7 T*m/A. Find the magnetic flux through the rectangular loop. Answer in units of Wb. http://img112.imageshack.us/img112/9541/mblf4.jpg [Broken] Shot at 2007-07-31 2. Relevant equations Magnetic flux = BA B = u * I / (2*pi*r) 3. The attempt at a solution I found the magnetic field B = u * I / (2*pi*r) = (4*pi*10^-7 * 36 A) / (2*pi * 0.03 m) = 0.00024 T Then I found the area of the rectangle which A = 0.075 * 0.15 = 0.01125 I multipled BA to get the magnetic flux. My final answer was 2.70e-6 Wb but this answer is wrong. Could someone please tell me what I'm doing wrong? Thank you.