In the above example the force on the current l is just given by F=1B, and its direction is to the left The lines of B are plotted in Fig. 13-2 These lines are under tension and repel each other laterally, giving rise to magnetic forces
13.2 Magnetic Pressure A current sheet carries a current density a(am pere/meter). It generates B B y fB. dI=pol, taking a closed path around the current, we have B+B=10, so the magnetic field generated on both sides of the sheet is B its direction: one side is upward, another side is downward.(both⊥toa)