1. 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