Two long, straight wires cross each other at right angles, as shown in the figure below. (Assume I1 = 4.70 A and I2 = 2.76 A.)
(a) Find the direction and magnitude of the magnetic field at point P, which is in the same plane as the two wires.
(b) Find the magnetic field at a point 30.0 cm above the point of intersection (30.0 cm out of the page, toward you).