1. The problem statement, all variables and given/known data A very long wire carrying a current I = 5.0 A is bent into a semi-circle with a diameter of 10 cm as shown in the figure. What is the magnitude of the magnetic field at the point P, halfway between the ends of the straight sections of wire and at the center of curvature of the semi-circle? http://ezto.mhecloud.mcgraw-hill.com/13252699451002736673.tp4?REQUEST=SHOWmedia&media=image015.png [Broken] 2. Relevant equations For the magnetic field due to a wire: B=(μ_0 * I) / (2 * pi * r) For the magnetic field due to the semi-circle: B= (μ_0 * I) / (4 * pi) 3. The attempt at a solution I said that the magnetic fields from both wires and from the semi-circle all point in the same direction, into the page. So I added up the magnetic fields from each component: (μ_0 * I) / (2 * pi * r) + (μ_0 * I) / (2 * pi * r) + (μ_0 * I) / (4 * pi) I get an answer that is not listed in the available choices. Where am I going wrong?