Why does the earth even have a magnetic field?

Why do compasses work if the Earth has such a weak magnetic field?

  • How do compasses work if the Earth has such a weak magnetic field? Seems like since Earth has only 1/2 a Guass of magnetic energy, it seems like compasses "should not" work since nowadays, our society has so many man-made things that generate much more magnetic power... Seems like magnetic interference would skew any compass in today's times.... but they don't... they seem to always work... so why? Serious answers please.

  • Answer:

    Indeed compasses do not work if close enough to other sources of magnetism than Earth's background magnetic field. BUT, if FAR ENOUGH from these other sources, then you can actually measure Earth's background magnetic field. There is a FALL-OFF of any magnetic field based upon distance from the source. Usually, it is inversely proportional to the distance, although it can become inversely proportional to the square of the distance, depending on the nature of the source of magnetism.

David J at Yahoo! Answers Visit the source

Was this solution helpful to you?

Other answers

The Earth's magnetic field is "relatively" weak, but is much stronger than anything we have built so far. The needle of a compass is highly magnetic, and with very little friction on the axle, and that's the only reason it works. Also, man made objects can sometimes divert it. Try using a compass on a metal bridge, and it will not work.

Tol'Satha

Just Added Q & A:

Find solution

For every problem there is a solution! Proved by Solucija.

  • Got an issue and looking for advice?

  • Ask Solucija to search every corner of the Web for help.

  • Get workable solutions and helpful tips in a moment.

Just ask Solucija about an issue you face and immediately get a list of ready solutions, answers and tips from other Internet users. We always provide the most suitable and complete answer to your question at the top, along with a few good alternatives below.