Why does negative charge reduce the potential of a metal plate in a capacitor?

AI Thread Summary
When a positive charge is applied to metal plate A, it induces a negative charge on the nearby plate B through electrostatic induction. This negative charge on plate B effectively reduces the potential of plate A, which in turn increases its capacitance as described by the formula C = Q/V. The presence of the negative charge creates a scenario where the entire system behaves like a neutral object, balancing the charges. The potential difference between plates A and B is influenced by the movement of electrons, which are attracted to the positive charge and thus reduce the potential available for discharge. Understanding this interaction clarifies why negative charge decreases the potential of plate A in a capacitor system.
logearav
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dear members,
when a positive charge is given to a metal plate say A, negative charge is induced on the nearby plate B(say) due to electrostatic induction. the presence of negative charge reduces the potential of the plate which increases the capacitance of A by the relation c=q/v. my question is why negative charge reduces the potential of A.
thanks in advance
 
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logearav said:
dear members,
when a positive charge is given to a metal plate say A, negative charge is induced on the nearby plate B(say) due to electrostatic induction. the presence of negative charge reduces the potential of the plate which increases the capacitance of A by the relation c=q/v. my question is why negative charge reduces the potential of A.
thanks in advance

According to me, with the B plate negatively charged, the whole system (A & B) is something like a neutral object. Look, a neutral atom consists of protons (in the nucleus) and electrons.
In fact the potential between A and B is increased.
 
Potential is simply "electron pressure". If you squeeze some electrons into a piece of metal, that repulsion is the pressure (potential) they are under. However, if you bring a positive charge near that piece of metal, that positive charge pulls the electrons toward some point on the object away from the lead wire attached to that object, reducing the force that would otherwise cause them to leave that object through the wire on the opposite side of the object.
 
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