BDL. Shown are 3 integration paths shaped like letters B, D, and L with enclosed identical currents with directions shown. What is the correct order of their line integral ?

Pawawell. Two straight, parallel wires carry currents in opposite directions. One wire has a current of 5.0 [A] while the other has 6.0 [A]. If the wires are spaced 4.0 [cm] apart, what is the force exerted by the wires on each other per unit length and what is their interaction?

Concentrix. Consider two concentric circular loops of radius and , respectively, lying in the -plane. Each loop carries a current moving in the directions shown. What is the magnitude of the net magnetic field at point at distance from the center of the loops?

Two lanes. Consider two current-carrying wires shown in the figure. The top wire at is carrying a current to the right and contains a charge element of width at . The bottom wire at is carrying a current to the left and contains a charge element of width at . What is the net magnetic field at due to these charge elements?

Singkil. Consider four long, straight, parallel wires arranged in the corners of a 20.0 [cm] square and are carrying currents directed as shown in the figure. The into the page currents are 5.0 [A], while the out of the page currents are 2.5 [A]. What is the magnitude and direction of at point , the center of the square?

Scattering charges. The figure shows a system of three electrons moving at velocities and a proton moving at velocity as shown. All charges are in the plane of the page (xy-plane). What is the magnitude and direction of the net magnetic field at point ?

Stability Check. Consider a circular loop shown which carry current in the direction indicated. If the loop is in a uniform magnetic field in the -direction, which of the following statements is/are TRUE about the loop?

I. The loop is in stable equilibrium.

II. The loop is in unstable equilibrium.

III. The loop experiences no torque.

Cross product check. A wire with a current along the -direction is under the influence of a uniform magnetic field along the -direction. Along what direction does the magnetic force on the wire segment point? 

Loop-in. A loop carries a current as shown and is immersed in a uniform magnetic field . What is the direction of the torque on the loop?

B-I-N-I-verse. A wire, bent as shown, is immersed in a uniform magnetic field 2.50 [T] directed to the right. The vertical segments are 1 [m] long while the diagonal segment is [m]. Current 4.00 [A] flows in the direction shown. What is the net force on the wire?