Charging by Contact: Calculating Charge on a Sphere after Multiple Contacts

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A small metal sphere with a charge of -2Q contacts three other spheres with charges +Q, +2Q, and +3Q sequentially. After each contact, the charges redistribute equally among the identical spheres. The net charge after the first contact is calculated to be -Q, resulting in each sphere having a charge of -Q/2. Following the same process for the subsequent contacts, the final charge on sphere T is determined to be +15/8 Q. The discussion emphasizes the importance of understanding charge redistribution in electrostatics.
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Electrostatics question, need help urgent!

Homework Statement


A small metal sphere carrying a charge of -2Q is first brought into contact with sphere R Which has a charge of +Q, and then into contact with sphere S which has a charge of +2Q, and finally into contact with sphere T which has a charge of +3Q. After making contact with the three spheres, in the stated order, the charge on the sphere at T is?


Homework Equations



F=kqQ/d^2

The Attempt at a Solution



Honestly, I've never learned how to do these sort of questions. I'd just like some insight on how to do these types of questions! any help is muchly appreciated ! please help, thankyou
 
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If the charged spheres are identical, the net charge will be shared equally by them. In the first case, after contact the net charge is -Q. So the charge on each sphere is - Q/2.
In similar way try the other cases.
 


Thank you. I understand how to do the question now. The answer is +15/8 Q.
 
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