Strange behaviour of a pithball when charged with a rubbed rod: Application Experiment

Aim

Use your model of charge, dielectrics, and conductors to explain what you see.

Prior Knowledge

• Nature of charge
• Conductors, dielectrics, and movement of charge

Description of the Experiment

A pithball (conductor) is suspended from a string. Observe what happens when a charged foam rod is brought close to the pithball. Then try and explain what you saw using your model of charge and how it moves.

In the second part of the video, the strings attached to the pithball are wetted with water. Observe what happens this time when a charged foam rod is brought close to the pithball. Use your model of charge and conductors to explain what you see.

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