A 6.0 m section of wire carries a current of 5.2 A from east to west in the earth's magnetic field of 1.0 × 10^-5 T at a location where the magnetic field points south. In which direction does the magnetic force act on the wire?

north, south, up, or down

?

Question

A 6.0 m section of wire carries a current of 5.2 A from east to west in the earth's magnetic field of 1.0 × 10^-5 T at a location where the magnetic field points south. In which direction does the magnetic force act on the wire?

north, south, up, or down

?

michele_laino · Answer

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anonymous · Answer

down?

michele_laino · Answer

we have to compute the magnitude of the magnetic field due to the wire

anonymous · Answer

how can we do that? what does it mean?

michele_laino · Answer

since we have to do a vector sum between the magnetic field of the wire and the earth's magnetic field

anonymous · Answer

ohh so it is moving south?

michele_laino · Answer

please sorry, it is not necessary to compute the magnetic field due to the wire

anonymous · Answer

ahh okie!

anonymous · Answer

so what does that mean? south is our solution?

michele_laino · Answer

the answer is up, since the magnetic forc acting on that wire is given by the subsequent formula:
$${\mathbf{F}} = I\;{\mathbf{l}} \times {\mathbf{B}}$$
where x stands for vector product.
So the direction of the force is up with respect to the plane of the drawing

anonymous · Answer

ohhh okay! :O thank you!! that makes sense:)

michele_laino · Answer

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