A small compass is held horizontally, the center of its needle a distance of 0.2
ID: 2109088 • Letter: A
Question
A small compass is held horizontally, the center of its needle a distance of 0.272 m directly north of a long wire that is perpendicular to the earth's surface. When there is no current in the wire, the compass needle points due north, which is the direction of the horizontal component of the earth's magnetic field at that location. This component is parallel to the earth's surface. When the current in the wire is 26.1 A, the needle points 20.9 ° east of north.
What is the magnitude of the horizontal component of the earth's magnetic field at the location of the compass?
Explanation / Answer
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