Consider a 0.85 m long conductive bar hanging from a pair of conductive springs attached at each end. The bar sits in a uniform magnetic field; the field is horizontally directed and perpendicular to the bar. If the spring constant for each spring is 75.0 N/m, the magnetic field strength is 0.16 T, and the bar carries a current of 12.0 A, by how much are the springs stretched when the current is on (as compared to when the current is off)?