A 1.5 m length of wire carrying 4.5 A of current is oriented horizontally in an East-West direction (conventional current flowing towards the West). At this point on the Earth's surface, the dip angle of the Earth's magnetic field makes an angle of 38 degrees to the wire. Estimate the magnitude of the magnetic force on the wire due to the Earth's magnetic field of 5.5*10-5 T at this point.
So you would use the equation ?F=ILxB?? where the x is the cross product. Plugging in current, length, and current field strength. What angle would you put in the equation as the cross product? My notes says 90 degrees, but I don't know why.