Magnetic force on power line carrying 110 A in Earth's field

[physicsed]

Homework Statement

A high voltage power line carries a current of 110 A at a location where the Earth's magnetic field has a magnitude of .59 G and points to the north, 72 degrees below the horizontal. find the direction and magnitude of the magnetic force exerted on a 250-m lengh of wire if the current in the wire flows (A) horizontally toward the east (B) horizontally toward the south.

Homework Equations

F= ILB SinX

The Attempt at a Solution

I= 110A B= .59 x 10^(-4) L=250

F= (110)(250)(.59 x 10^(-4))(sin -72)
F= -1.543
Is it correct or not! i need to know the answer. can someone please help me.

 

[tongpu]

I think you should break the magnetic field into components becasue 72 degree is not the angle between ILXB.

 

[physicsed]

how should i break it down?