Magnetic

• A magnetic field is the distribution of a magnetic force in the region of a magnet.
• As with electric fields, there are two different magnetic characteristics, labelled north and south.
• Metals like iron, nickel, and cobalt, or mixtures of these three are called the ferromagnetic metals.
• Earth acts like a giant permanent magnet, producing its own magnetic field.
• Lifting electromagnet, relay, electric bell are the uses of electromagnets.
• Similar magnetic poles, north and north or south and south, repel one another with a force at a distance.
• Dissimilar poles, north and south, attract one another with a force at a distance.
• Oersted's principle: charge moving through a conductor produces a circular magnetic field around the conductor.

Right hand rule:

• For conventional current flow grasp the conductor with the thumb of the right hand pointing in the direction  of  conventional or positive, current flow. The curved fingers point in the direction of the magnetic field around the conductor.
• Grasp the conductor with the right hand such that curved fingers point in the direction  of  conventional or positive, current flow. The thumb points in the direction of the magnetic field within the coil. Outside the coil, the thumb represents the north end of the electromagnet produced by coil.