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if work is done along the direction of force,then the work is regarded as positive work and if work is done in a direction opposite to the direction of force then it's regarded as negative work.Whereas in electrostatics, if a positive charge is brought near a positive charge(which produces an opposing force) the work(electric potential) is regarded as positive and if the same positive charge is brought near a negative charge then the its regarded as negative work(potential).Just the opposite

Aravindh Vasu
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Whereas in electrostatics, if a positive charge is brought near a positive charge(which produces an opposing force) the work(electric potential) is regarded as positive.

Here, the work done by the external force (which is you pushing the charge) is positive, cause you displace the charge along the direction in which you apply force. On the contrary, the work done by electrostatic repulsive force is negative ...

and if the same positive charge is brought near a negative charge then the os regarded as negative work(potential)

Here, you the force is attractive. When you are included (an external force), it always implies an opposite force to the electrostatic force. So the positive charge eventually displaces into the direction of negative charge. But you try to pull it upwards ... You need not push it towards the negative source as the force here is already attractive ...

MarianD
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Nehal Samee
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It's not the opposite. It's exactly the same.

First, you always have to declare which force you are talking about when you talk about work. You don't, but the context implies that in both of your examples you mean the force that you apply in displacing the object. In both cases the sign of work is determined by the relative directions of the force you apply and the displacement of the object that you are pushing. Electric potential has nothing to do with the work done by the force you apply.

The work you do in bringing a positive charge to a positive charge is positive. Your hand pushes in the same direction as the displacement. But there's another force in play in this scenario: the work done by the other charge on the charge that you are displacing. That work is negative. The electrostatic force points in the direction opposite to the displacement.

The concept of potential applies to the work done by the opposing charge. Potential is defined in terms of potential energy $$V=U/q$$ But potential energy is defined in terms of work done by the internal force$$ U=-W_\mathrm{internal}$$ The internal work in the case at hand is the work done by the field of the other charge in displacing a charge. There is no mention of external applied forces in the definition of potential energy and potential.

garyp
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