(a)[3]
On Fig. 8.2, draw the magnetic field pattern produced by the current-carrying wire in plane EFGH.
(b(i))[2]
Calculate the magnetic flux density at wire Q produced by the current in wire P.
(b(ii))[2]
Calculate the force per unit length, in $\text{N m}^{-1}$, on wire Q caused by the current in wire P.
(c)[2]
The currents in wires P and Q are different in magnitude. State and explain whether the forces per unit length on the two wires will differ.