|
Charging by Induction:
Charging by induction is a charging process that involves charging an object without touching the object to a charged object. The charged object is brought near to the object to be charged (a neutral object). The charged object's presence induces a movement of electrons within the neutral object, causing it to become polarized. Then the neutral object is touched to a ground, causing a transfer of electrons between ground the neutral object. The ground is pulled away, the charged object is pulled away and the neutral object has been charged. When the process is complete, both objects are charged with the opposite type of charge.
|
|
Opposites attract. Likes repel. And only electrons can move. That's the key to understanding charging by induction. The role of the charged balloon in the induction charging process is to induce a movement of electrons within the nearby can X. A negatively charged balloon will repel electrons and a positively charged balloon will attract electrons. Since the pop cans consist of conducting materials and are touching each other, the movement of electrons does not end or start at the edge of can X. Electrons can move from can X to can Y or vice versa. This movement of electrons causes the two cans to be polarized. Knowing which direction electrons move is a simple matter of applying the slogan opposites attract and likes repel.
|
|
Many students have the misconception that induction charging involves the transfer of electrons between the charged object and the object being charged. But don't be fooled! There is no such electron movement. In this question, the charged balloon is brought near to the pop can but does not touch it. The can and the balloon are separated by a few centimeters of air. Air is an insulator. Electrons need a conducting pathway in order to move from one location to another. The insulating qualities of air prevent this movement of electrons.
|