Force on Currents: a Thin Copper Rod That Is 1

Multiple Choice

Force on currents: A thin copper rod that is 1.0 m long and has a mass of 0.050 kg is in a magnetic field of 0.10 T. What minimum current in the rod is needed in order for the magnetic force to cancel the weight of the rod?

A) 1.2 A
B) 2.5 A
C) 4.9 A
D) 7.6 A
E) 9.8 A