Problem $5$

A$)$ There is a very long wire with a current of $21$ upward. Calculate the magnetic field $10$ cm away on the right side of the wire.

B$)$ Now a second very long wire is placed $20$ cm away from the $21$ wire with a current moving in the opposite direction. Determine the magnitude of the force per unit length on the wire with current I.

C$)$ What direction does the wire with current I move, if at all?

D$)$ Now a third very long wire is placed $30$ cm away with a current $($I$)$ moving in the opposite direction as the first wire. Determine the magnitude of the force per unit length on the center wire.

E$)$ What direction does the on the center wire move, if at all?