# Homework Help: Magnetic field with a split current

1. Nov 20, 2012

### bfusco

1. The problem statement, all variables and given/known data
A circular conducting ring of radius R is connected to two exterior straight wires at two ends of a diameter. The current I splits into unequal portions while passing through the ring. What is the magnitude of B at the center of the ring?

3. The attempt at a solution
My problem isnt with solving the question, it's with which equation to use. i originally did it using the equation finding B in a wire B=μI/2∏R, however that is apparently the incorrect equation. the equation is B=μI/4R, i dont know what the equation is, and considering the problem is of a current carrying wire that splits into 2 wires (where the current is distributed unequally) then reconnects to form a single wire again. i would think you would use the equation to find B in a wire.

If someone could explain why i am suppose to use the B=μI/4R equation and what it is i would appreciate it so much.