A 15 cm length of conductig wire that is fee to move is held in place between two conducting wires. All the wires are in a magnetic field. When a 5 A current is in the wire, the wire segment moves upward at a constant velocity. Assuming the wire slides without friction on the two vertcal conductors and has a mass of 0.15 kg, calculate the magnitude and direction of the minimum magnetic field thatis required to move the wire.

What equations do I need to use?
Please and thank you. Sorry for any typos.

Question

A 15 cm length of conductig wire that is fee to move is held in place between two conducting wires. All the wires are in a magnetic field. When a 5 A current is in the wire, the wire segment moves upward at a constant velocity. Assuming the wire slides without friction on the two vertcal  conductors and has a mass of 0.15 kg, calculate the magnitude and direction of the minimum magnetic field thatis required to move the wire.

What equations do I need to use?
Please and thank you. Sorry for any typos.

anonymous · Answer

force in magnetic field, assuming B is perpendicular to the current
F=B.I.L
and you have weight of the wire in opposite direction, so it moves in constant velocity
B.I.L=mg, findB