Magnetism and Electromagnetism

17.1 The Magnetic Force - Another Force at a Distance

Magnetic field: Is the region where the magnetic force of a magnet is distrbuted.
This pictures shows the magnetic field of magnet with iron powder, as you can see the field in around the north and south side of the magnet.

If two magnets are facing each other on the opposite pole they would attract. Meaning that if north and south pole were facing each other they would attract like in the picture. But if the same poles would face each other, they would repel.

Magnetic forces don't just work on magnets, they also work on different metals. These metals are called ferromagnetic metals.
Domain Theory: This theory stats that all large magnets are made up of smaller and rotatable magnets, dipoles, which interact with each other. If these dipoles a line, then a magnetic domain is formed.

Electromagnets
Oersted's Principle: Oersted discovered that charges moving through a conductor produces a circular magnetic field around the conductor.
By knowing this information, we have been able to developed several hand signs to help predict how magnetic forces act.

Right Hand Rule
 First right hand rule for conductors: This rule can be used to find the direction of the current or the direction of the magnetic field if one of the factors are given. For example, if the current was moving left, then the magnetic field would be clock-wise.

As shown in the picture, the thumb would point in the direction of current flow while the curl of the figures would show the magnetic field.








Right Hand Rule # 2
This rule can be applied to a coiled wire conductor. This is done to strengthen the magnetic field by coiling the wire in a linear cylinder. This second right hand rule is to find the conventional current flow and the north side of the field.

For example, if the finger curls point in the direction of the current, inward, then the north side of the field is left. This north side of the field is represented by the direction the thumb is pointing.