Find current given magnetic field

[ooohffff]

Homework Statement

Suppose a straight 1.90 mm diameter copper wire could just "float" horizontally in air because of the force due to the Earth's magnetic field [PLAIN]http://www.webassign.net/images/boldB.gif, which is horizontal, perpendicular to the wire, and of magnitude 4 ✕ 10-5 T. What current would the wire carry?

Homework Equations

F = ILB

The Attempt at a Solution

It seems like a simple question but the phrasing is a bit confusing and I'm having trouble visualizing it. So the F vector is pointing up in the k-direction because it's pushing the wire up, right? The B vector is horizontal so let's say in the i-direction, but how is it perpendicular to the wire if the wire is also floating horizontally?

So far, all I could do is rearrange the force equation to
I=F/LB

 

[ooohffff]

Also, I believe F should be equal to F_g since the wire is floating in the air.

Ah, also I think B should be going into the page?

 

[ooohffff]

So update:

I = 9.8N/ L*(4x10^-5 T)

How am I supposed to get L?

 

[rude man]

So update:

I = 9.8N/ L*(4x10^-5 T)

How am I supposed to get L?

Where did you get 9.8N from? You're implying (whether you know it or not) that your wire has mass of 1 kg. So what's the length of 1 kg of Cu wire with diameter 1.9mm?[/QUOTE]