Consider a bar magnet with magnetic moment m, suspended horizontally in a region where there are two perpendicular horizontal magnetic fields, and external field B and the horizontal component of the earth’s field BH. If no external magnetic field B is present, the bar magnet will align with BH. Due to the field B, the magnet experiences a torque τD , called the deflecting torque, which tends to deflect it from its original orientation parallel to BH. If θ is the angle between the bar magnet and BH, the magnitude of the deflecting torque will be,