What Happens to the Charge When Two Insulated Spheres Touch?

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When two insulated metal spheres with charges of +10 micro C and -5 micro C touch, they share their charges and reach equilibrium while maintaining charge conservation. Sphere A, with twice the radius of sphere B, will have a larger surface area to accommodate more charge. After contact, sphere A's charge decreases to +7.5 micro C, while sphere B's charge increases to -2.5 micro C. Once separated, these final charges remain unchanged. Understanding this process is key to grasping electrostatics in physics.
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I have just started electricity in physics and am wondering how to do this homework questions.

The question is:

Sphere A and B are insulated metal spheres with charges of +10 micro C and -5 micro C respectively. If sphere A has twice the radius of sphere B, what will be the charge on each sphere after they are touched together and then separated.
 
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HINT:When being put in contact (and afterwards as well) the two spheres must have the same electric potential.

Daniel.
 


Hi there! It's great that you are learning about electricity in physics. The homework question you have asked is related to electrostatics, which deals with the study of electric charges and their behavior. To solve this question, we need to understand the concept of charge conservation, which states that the total charge in a closed system remains constant.

In this question, we have two insulated metal spheres, A and B, with charges of +10 micro C and -5 micro C respectively. When these two spheres are touched together, they will share their charges and reach a state of equilibrium. This means that the total charge of the system will remain the same, but it will be distributed differently between the two spheres.

Since sphere A has twice the radius of sphere B, it will have a larger surface area and can accommodate more charge. So, after they are touched together, the charge on sphere A will decrease from +10 micro C to +7.5 micro C, while the charge on sphere B will increase from -5 micro C to -2.5 micro C.

After they are separated, the charges on the two spheres will remain the same as they were after they were touched. So, the final charges on sphere A and B will be +7.5 micro C and -2.5 micro C respectively.

I hope this helps you understand how to approach this homework question. Keep practicing and exploring the fascinating world of electricity and electrostatics!
 
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