A bar magnet is suspended so that it is free to be swung vertically. Which direction would the north pole of the magnet point: a.) in the southern hemisphereb.) in the northern hemisphereand why?
The north pole of a suspended magnet that is free to swing will always point North, both in southern or in northern hemisphere.
This is because Earth is a magnet with the North and South poles, just like any bar magnet. The south magnetic pole of Earth is located close to the geographic North Pole of Earth. Since south and north poles of two magnets attract (and the like poles repel), the north pole of any bar magnet, such as a compass needle, will point towards the geographic North.