# Cancelling magnetic fields#

Two long wires, one of which has a semicircular bend of radius $$R$$, are positioned as shown in the figure.

## Part 1#

If both wires carry a current $$I$$, how far apart must their parallel sections be so that the net magnetic field at P is zero?

In your symbolic expression, use pi to represent Ï.

## Part 2#

What is the direction of the current in the straight wire on the right-hand side?