Using Ampere's Law in finding H (magnetic field intensity)

[jadi929]

Homework Statement

Let the regions 0 < z < 0.3 m and 0.7 < z < 1.0 m be conducting slabs carrying uniform current densities of 10 A/m^2 in opposite directions. Find H (the magnetic field intensity) and different z positions.

Homework Equations

Biot-Sarvot Law: H = ∫ (I dL X r)/ (4∏R²)

Ampere's Circuital Law: ∫ HdL = I

The Attempt at a Solution

I am guessing we have to apply ampere's law to each slab, in a rectangular loop. The slabs extend infinetly in the y and x axes. But I got no clue on exactly how to apply this law :( Any help would be appreciated as this my first post here.

Thanks!

 

[vela]

Good idea. Surely your textbook has examples of how to apply Ampere's law.