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What Is Voltage


What Is Voltage


Energy is required for the movement of charge from one point to another. Let W joules of energy be required to move a positive charge of Q coulombs from a point a to point b in a circuit. We say that a voltage exists between the two points. The voltage V between two points may be defined in terms of energy that would be required if a charge were transferred from one point to the other. Thus, there can be a voltage between two points even if no charge is actually moving from one to the other. the voltage between a and b is given by 



                                    V=W/Q J/C



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