- #1

Angie K.

- 108

- 1

## Homework Statement

A long pair of wires serves to conduct

*I*= 25.2 A of dc current to and from an instrument. If the wires are of negligible diameter but are

*d*= 2.92 mm apart,

what is the magnitude |

*B*| of the magnetic field a distance

*L*= 9.5 cm from their midpoint, in their plane?

What is the ratio |

*B*|/|

*B*Earth|, where |

*B*Earth| = 5.0 × 10-5 is the magnetic field of the Earth.

## Homework Equations

B = mu0*I/2pi*r

## The Attempt at a Solution

[/B]

I know that to find B it's just a matter of plugging in the current into the equation above and the r I am not sure about. Someone please clarify this for me?