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

In summary, brass rods cannot be charged by rubbing because they are conductors and charge generated by friction is quickly dispersed. Not all rubbing materials can charge a brass rod, as materials with higher electronegativity are more effective. Insulating a brass rod can prevent charge dispersal, but it is still unlikely to result in a significant build-up of charge. Materials with higher electronegativity, such as glass and rubber, charge easily through rubbing, while those with lower electronegativity, like brass, do not. Brass rods can also be charged through methods such as induction and contact with a charged object.

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?

FAQ: Why Can't Brass Rods Be Charged by Rubbing?

Why can't brass rods be charged by rubbing?

Brass rods cannot be charged by rubbing because they are considered to be conductors. Conductors are materials that allow electric charges to flow through them easily. When a brass rod is rubbed, the charges generated by friction are quickly dispersed throughout the rod, preventing any significant build-up of charge.

Can any type of rubbing material charge a brass rod?

No, not all rubbing materials can charge a brass rod. Brass rods are typically made of copper and zinc, which have a high conductive ability. Materials that have a higher degree of electronegativity, such as glass or rubber, are better suited for charging objects through friction.

Is it possible to charge a brass rod by rubbing if it is insulated?

Insulating a brass rod can help to prevent the dispersal of charges generated by rubbing, but it is still unlikely to result in a significant build-up of charge. Insulators do not allow charges to flow through them easily, but they can still transfer charges through direct contact with a conductor.

Why do some materials, like glass and rubber, charge easily through rubbing while others, like brass, do not?

Materials that charge easily through rubbing tend to have a higher degree of electronegativity, meaning they have a greater tendency to attract or hold on to electrons. This allows them to easily transfer charges to and from other materials, resulting in a build-up of charge. Brass, on the other hand, has a lower electronegativity and is therefore less effective at generating and transferring charges through friction.

Can brass rods be charged in any other way besides rubbing?

Yes, brass rods can be charged through other methods such as induction or contact with a charged object. Induction involves bringing a charged object near the brass rod, causing the charges within the rod to rearrange and create a temporary charge. Contact with a charged object can also transfer charges to the brass rod, resulting in a build-up of charge.