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Basic Characteristics of Magnets
In the first place, what is a magnet?
Attracting steel and pointing south and north are generally known, but by examining deeper, we can reach some rule, and equations for the attraction and repulsive forces appear.
Every magnet has a N pole and S pole without exception. On the contrary, there is no magnet with only a N pole or S pole. The magnetic attraction works between different poles, and the repulsive force works between the same poles.
Every magnet has a N pole and S pole without exception. On the contrary, there is no magnet with only a N pole or S pole. The magnetic attraction works between different poles, and the repulsive force works between the same poles.
Rule of Coulomb
What is the Coulomb force?
By rubbing hair with a plastic sheet and raising the plastic sheet a little bit, the hair may stand up toward the plastic sheet or stick to the plastic sheet. This is because the power to attract each other works between the plastic sheet and hair.
The source of the attraction force is called an “electrical charge”. By rubbing hair against a plastic sheet, one side receives a positive electrical charge and the other side receives a negative electrical charge. The positive and negative charges pull against each other, so the phenomenon that hair and the plastic sheet pull against each other is called the Coulomb force.
How the Coulomb force is communicated has a specific rule. It is proportional to the product of electric charges and in inverse proportion to the square of the distance. This rule is called the rule of Coulomb.
【The formula for the attraction and repulsive forces is below.】
