Slight redistributions in the Earth's mass cause changes in the moment of inertia, which are reflected in slight changes in the rotation rate. And besides these short-term events, there a long-term sl...Slight redistributions in the Earth's mass cause changes in the moment of inertia, which are reflected in slight changes in the rotation rate. And besides these short-term events, there a long-term slowing of the Earth's rotation due to tidal friction, so that days are becoming gradually slower over the long term. In addition, the direction of the Earth's axis itself is moving around in a complicated way; the resulting motions of the axis, called precession and nutation, will be described here.
A magnetic pole is the north or south end of a magnet, where the magnet exerts the most force. However, it is called the north magnetic pole because it is close to the north geographic pole. Launch th...A magnetic pole is the north or south end of a magnet, where the magnet exerts the most force. However, it is called the north magnetic pole because it is close to the north geographic pole. Launch the PLIX Interactive below to learn more about how a compass utilizes the Earth’s magnetic field and observe what happens to a compass as you change positions on Earth: Earth acts as a giant magnet with magnetic poles and a magnetic field over which it exerts magnetic force.
