Why Can't Brass Rods Be Charged by Rubbing?

Thread starter perjogab
Start date Dec 1, 2008
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Electricity Static Static electricity

AI Thread Summary

Brass rods cannot be charged by rubbing because they are conductors, allowing electric charges to move freely across their surface. In contrast, polythene is an insulator, which retains the charge when rubbed. When a conductor like brass is rubbed, any charge that might be generated is quickly dissipated. Therefore, brass does not accumulate a static charge in the same way that insulating materials do. Understanding the difference between conductors and insulators is crucial for grasping electrostatic charging principles.

Dec 1, 2008

perjogab

Hey guys, I have a physics exam tomorrow. I found a question that I can't solve.

Rubbing a polythene rod with a cloth makes the polythene negatively charged but rubbing a brass rod in this way will not charge it. Why can't the brass rod be charged this way?

Thanks

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Dec 1, 2008

turin

Homework Helper

Would you consider brass to be a conductor or an insulator?

Dec 1, 2008

perjogab

Brass is a conductor isn't it?

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