Magnetic fields and current flows

[liz_p88]

Homework Statement

A 2.50 meter long copper rod has a mass of 0.25 kilograms. A magnetic field of 0.15 Teslas is oriented horizontally from south to north. a.) What is the minimum current in the rod that would allow it to "levitate" in this magnetic field? b.) What is the direction of the current in the wire?

Homework Equations

F = mg
F = ILB
ILB = mg

The Attempt at a Solution

I = mg/(LB)

(.25kg)(9.8m/s^2)/(2.5m)(.15T) = 6.533 A, East

I'm not sure if I did this correctly

 

[supratim1]

yes you are correct.

 

[liz_p88]

Thank you! I doubt myself so much. I have to work so hard to understand these concepts and formulas

 

[supratim1]

yes, work hard and you will gain confidence.