Is Work Done by a Voltage Source Positive or Negative When Current Opposes EMF?

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The work done by a voltage source is considered negative when the current flows against the electromotive force (EMF). This is because the voltage source receives energy as current enters its positive terminal, resulting in a gain of energy. While the power associated with the voltage source is positive, indicating energy is being stored, the work done by the source itself remains negative. Conversely, the work done on the source is positive, as it reflects the energy input into the system. Overall, the distinction lies in the direction of energy transfer relative to the voltage source.
hackhard
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Is the work done by a constant voltage source positive or negative when current is opposite to emf?
 
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Dale said:
Negative
when current enters positive terminal of voltage source, voltage source charges up , so it gains energy , its power(energy derivative) is positive
shoudnt work done (power integral)be positive?
 
Work done by the voltage source is negative because it receives energy.
Work done by whatever current source you have, is positive.
 
hackhard said:
when current enters positive terminal of voltage source, voltage source charges up , so it gains energy , its power(energy derivative) is positive
shoudnt work done (power integral)be positive?
Work done on the source is positive. You asked about work done by the source, which is negative.
 
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