Help with negative charges in an electric field.

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How can a negative charge move towards a position of a higher electric potential from lower potential but lose electric potential energy?


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From my understanding, I understand that for a positive charge, it must lose potential energy from the electric field as work is done by the electric force in the direction of the E-field as seen in the diagram. This can be seen as it moves from high electrical potential energy to low potential energy. However, for a negative charge, it would do work up this electric field. I do not understand how it can do work and as the diagram suggests gain electrical potential energy as it moves up to a higher potential energy.
 

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PeroK
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Potential in Electrostatics is not the same thing as potential energy. Your argument essentially shows this.

The direction of the force on negative and positive charges is opposite. The formulation of potential energy in the two cases, therefore, must be different for the same electric field.
 
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RPinPA
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The diagram is not correct for a negative charge. The field and potential difference are the same, those are caused by other charges external to ##q##. But the force it feels is toward the positive terminal, and the potential energy ##U = qV## is lower when ##V## is higher, at the positive terminal. In that diagram a negative charge moving downward is moving against the force. It would have to do work against the force to gain potential energy and thus lose kinetic energy.
 

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