Two completely opposite objects that can actually cause an attraction?
You must have done this at some point in your life, where you take a balloon and rub it all over your hair, and then as a result, as you pull the balloon away, your hair sticks to the balloon. Now did the balloon excrete some sort of sticky liquid that caused your hair to adhere to the balloon? No, that’s just nasty. It’s caused by the attraction that occurs between the two objects.
How does the attraction work?
This attraction occurs because of a concept called conduction. Remember that all objects have inherent charge associated with them because they are made up of positive and negative charges. The ones that have an equal amount of both of these charges are considered neutral. Both the balloon and your hair are neutral before the attraction. But, when the balloon is rubbed against your head, conduction occurs where the once neutral objects begin to take on actual charge.
When the rubbing action occurs, the negative charges from your hair get transferred over to the balloon thus making the balloon more negative and your hair more positive. This is what causes the initial attraction between the balloon and your hair since opposite charges attract.
What else can you do with the balloon?
Now that the balloon is full of negative charges, if you were to bring it over to another neutral object, you would notice that the balloon may cause another attraction without even touching it. This is due to a concept called induction. Induction occurs when a charged object is brought close to a neutral object and induces/causes there to be a charge separation and therefore an attraction.
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