A current-carrying wire has been bent into the form shown in Figure P28.74, with a half-circle of radius \(R_{1}\) lying in the \(x y\) plane connected via two straight segments to a half-circle of radius \(R_{2}\) lying in the \(y z\) plane. The current direction is as indicated. If \(R_{2}=1.5 R_{1}\), what is the direction of the magnetic field at \(\mathrm{P}\), which lies at the common center of the half-circles?

Data from  Figure P28.74

Figure P28.74 R R,