Opposites Attract Creating A Force...

We recently started our new unit on magnetism. Starting from elementary school, we all have played with magnets; knowing that like poles (same charge) repel and unlike poles (opposite poles) attract. To test this theory we used a compass to detect the direction of north and south using a magnet. It was not showing expected results; the north was attracting to the north and south to the south. So we learnt that the earth's actual north pole is not in the arctic it is in the antarctic and the south is actually in the arctic. This concept can be more clearly observed in the below diagram.

                This constant change in the magnetic fields is causing animals who have natural sense of direction to lose their way and eventually leads to their death.

Scientists in the early days were trying to research force at a distance which was the common element between electrostatics and magnetism. Among one of them was Hans Christian Oersted. While conducting his research, he discovered something very significant which came to be known as Oersted's Principle.

Oersted's Principle: Charge moving through a conductor produces a circular magnetic field around the conductor

Using this knowledge from Oersted, scientists were able to develop right-hand rules (called right hand because the use of the right hand is involved).

Right Hand Rule # 1: If the right hand is placed around the conductor with the thumb pointing in the direction of conventional current flow, or positive (+) current flow, the fingers will curl in the same direction as the magnetic field.

               In this case the thumb is pointing upwards and the fingers are curled pointing to the right. This indicates that the magnetic fields will go to the right in other words counter clockwise.

Right Hand Rule # 2: The fingers curl in the direction of conventional current, or positive (+) current flow and the thumb points in the direction of the magnetic field within the coil. Outside the coil, the thumb represents the north (N) end of the electromagnet produced by the coil.

                    In this case the fingers are curled upwards, making the thumb point to the left. This indicates that the  north (N) pole is on the left side of the coil.

Later we can learn how these two rules strengthen our knowledge of magnetism and can enable us to make things move using electricity such as a motor!