1 2 Phy432 Midterm Test: March 4, 2010 Name: Fig. 1 Fig. 2 Fig. 3 Find the vector potential at a point P on the axis of a circular loop of radius R, which carries a steady current I (Fig. 1). 2. The magnetic field in region 1, close to the interface between media 1 and 2 is B. The surface current at the boundary is K (Fig. 2). Find the magnetic field in region 2 close to the boundary At what value of K the magnetic field in region 2 vanishes? Fig. 1 1 2 Fig. 2 3. A long straight wire carrying a steady current I, lies along the axis of a linear paramagnetic cylinder of radius R and permeability m (Fig. 3). Ignore any end effects that might occur due to the finite length of the cylinder. Find H, B and M inside and outside the cylinder. Compute all bound currents flowing in the cylinder. Fig. 3 4. For the RLC circuit shown in Fig. 4, find the impedance of the parallel RLC circuit the amplitude of the current I Fig. 4