Voltage, or the Desire to be Somewhere
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Voltage, as defined by Knight in the textbook, "is a property of the source charges" which results in a force on a charged particle. Most electric power sources are voltage sources meaning the voltage drives the circuit.
Instead of charged particles we have negative people and instead of a voltage let's say there is a concert that they all want to go to. The concert probably will play some sad songs that have a pessimistic view on life which will help fuel their negativity. Now if the artists performing are really good then the people will want to go more than if the performers aren't as good. This desire to go is the equivalent of voltage. The desire to go to the concert is what drives these sad, sad people.