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Mission SE5 Charging by Induction - Pop Can Induction

 The Question

Two neutral conducting pop cans are touching each other. A negatively charged balloon is brought near one of the cans. The cans are separated while the balloon is nearby. After the balloon is removed, the balloon is ____.

 Physics Rules

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.

 Think About It

For an object such as the charged balloon to become more charged or lose its charge, there must be a transfer of electrons between it and another object. In the charging by induction process, electrons move between can X and can Y. Electrons do not move between the cans and the charged object. Whatever charge the balloon had before the induction process began is the charge it will have afterwards. The balloon is simply used to induce a movement of charge within the object that is being charged. It never serves to supply or receive electrons from it.

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