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Young Voices for the Planet DVD in our online store includes 8 films where students speak out and take action on climate change.

The Force of Magnetism

You may ask, how does the force of Magnetism work? The force of magnetism is directed from one pole to another. A pole can be described as the point where lines of magnetic force come together.

Most simple magnets have two poles (that makes them "di-poles"), as shown in this picture. The magnetic field "lines" illustrate where the force of magnetism is, and whether it is stronger (red) or weaker (blue).

This is an illustration of how magnetism works. Click on images for full size version (40K GIF)
For simple magnets, the force of magnetism works in the following way: When two magnets are brought together, the force will attract the two magnets together if the poles are opposite, that is if the pole of the first magnet is positive and the pole of the second magnet is negative. If that condition is true, the two magnets will be "forced" to stick together.
If two magnets of the same polarity are brought together, the force of magnetism will repel the two magnets from each other, and they cannot be made to stick together.

Shop Windows to the Universe Science Store!

Our online store includes issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, ranging from seismology, rocks and minerals, oceanography, and Earth system science to astronomy!

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

The Magnetic Field

The force of magnetism causes material to point along the direction the magnetic force points. As shown in the diagram to the left, the force of magnetism is illustrated by lines, which represent the force....more

The Earth's Magnetic Field

The Earth has a magnetic field with north and south poles. The Earth's magnetic field reaches 36,000 miles into space. The magnetic field of the Earth is surrounded in a region called the magnetosphere....more

Earth's Magnetic Poles

Earth has a magnetic field. If you imagine a gigantic bar magnet inside of Earth, you'll have a pretty good idea what Earth's magnetic field is shaped like. Of course, Earth DOESN'T have a giant bar magnet...more

Earth's North Magnetic Pole

Earth has a magnetic field with a north pole and a south pole. Earth's magnetic field is pretty much (but not exactly) like the magnetic field around a bar magnet. Earth's North Magnetic Pole (NMP) is...more

Planetary Magnets

The Earth is a good example of a planetary dipole, where the lines of force point in a direction out of the South (magnetic) Pole and into the North (magnetic) Pole. Planets can also show evidence of quadrupoles...more

Detecting Planetary Magnetism

A magnetometer is an instrument for measuring magnetic fields. Many spacecraft carry magnetometers to measure the magnetic fields around planets. When a spacecraft makes those measurements, what do the...more

Electricity and Magnetism

Electricity and magnetism are two very important topics in the science of physics. We use electricity to power computers and to make motors go. Magnetism makes a compass point North and keeps notes stuck...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information.