A conducting wire of circular cross section formed of a material that has a mass density of 2.7 g/cm^3 is placed in a uniform magnetic field with the axis of the wire perpendicular to the direction of the field. A current density of 2.4*10^6 A/m^2 is established in the wire and the magnetic field increased until the magnetic force on the wire just balances the gravitational force. Calculate the value of B when this condition is met.