EXPLORING MAGNETISM

What is a Magnet? A magnet is an object that possesses the property of attracting iron or materials containing iron.

What Materials are Magnetic?

Properties of Magnets All magnets have a north and south pole. Like poles repel, opposite poles attract. If you break a magnet, you get two smaller magnets. Magnets exert a magnetic force field. Electric fields can induce magnetism. Magnetic fields can induce electrical currents

What Makes a Magnetic Field All materials are made up of atoms. In these atoms electrons move around the nuclei of the atoms. It is this motion that creates small magnetic fields. is made up of atoms creates small magnetic fields.

Making a Magnet Takes Organization. Non-magnet Every atom makes it’s own magnetic field. For non-magnets these fields points in all directions, canceling each other out so that there is not net field. In magnets most of these fields point in the same direction, creating a strong net magnetic field. Magnet Magnetic Domains are clusters of atoms the have their magnetic field pointing in the same direction

Earth: A Huge Bar Magnet Moving molten iron in Earth’s outer core causes most of Earth’s magnetic field. Magnetic field poles are NOT aligned with geographic poles. They also wander and flip (500,000 yrs between flips, 10,000 yrs to complete flip).

Electricity and Magnetism Electric Current (Electricity) is moving charge. In an electric circuit, batteries provide an electric field to push charges through a wire. The wire provides a path for charges to flow. Unless there is a complete circuit the charges cannot flow. Magnets can push or pull on a wire with current flowing through it.

Electricity and Magnetism A dynamic electric field creates a magnetic field. A dynamic magnetic field creates an electric field. The basic principle behind electric generators is creating relative motion between a magnet and a wire to create an electric field that will push current through a circuit. Converts mechanical energy into electric energy.

Electromagnetic Radiation Electromagnetic waves are created by the vibration of an electric charge. This vibration creates a wave which has both an electric and a magnetic component. 

Electromagnetic Spectrum Electromagnetic waves travel through empty space at a speed of 300,000 km/s (186,000 miles/sec).