1. The problem statement, all variables and given/known data Consider an infinite sheet of parallel wires. The sheet lies in the xy plane. A current I runs in the y-direction through each wire. there are N/a wires per unit length in the x direction. Write an expression for B(d) the magnetic field a distance d above the x y plane of the sheet and we have to express the magnetic field as a vector. 2. Relevant equations Ampere's Law --> closed integral of (Bdl) = uIencl 3. The attempt at a solution I know that by using the right hand rule, the magnetic field would pointing in the negative x direction if i pick a point above the surface. Then I tried to figure out what Iencl is and I get I = (N/a)(a)(I) = NI Then using ampere's law I get B(top integral + bottom integral) = uNI B(2a) = uNI B= UNI/2a and since the magnetic field is heading towards the negative x direction I typed in B = -(uNI)/2a x Please help! I don't know what I'm doing wrong! Thanks!