Understanding Potential Difference and EMF in Electric Circuits

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Potential difference in a circuit refers to the work done by the electric field to move a charge between two points, while electromotive force (EMF) indicates the energy supplied per unit charge by a source. The potential difference can be considered negative when electrons lose energy, whereas EMF is positive as it represents energy gained. When measuring potential at a point in a circuit, the value after a resistor reflects a potential difference, as it indicates a drop in voltage due to resistance. Understanding the distinction between EMF and potential difference is crucial for analyzing circuit behavior.
tonyjk
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hello... potential difference between two points in a circuit is the work done by the electric field to get a charge from point to another and for the emf it's also the work done but my question is for a potential difference the work is negative( the electrons lose energy) and for the emf the work done is positive( the electrons gain energy) ? or what? and the potential measured between a point of a circuit and the ground is it an emf or a potential difference( so it's like a given energy or a loss of energy)? thank you:D
 
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i have read some threads made here but i didnt 100% get the response through them so please if any of the admins or members can help me.. thanks again
 
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Emf, voltage, electric charge, potential (difference), seems to refer to the more or less the same form of energy. They fade doing work if the energy is not renewed.
 
so the emf and potential difference are the same in a circuit? they have the same effects?
 
Voltage is electric potential energy per unit charge, measured in joules per coulomb ( = volts). It is often referred to as "electric potential", which then must be distinguished from electric potential energy by noting that the "potential" is a "per-unit-charge" quantity.

The emf represents energy per unit charge (voltage) which has been made available by the generating mechanism and is not a "force".

This is a good explanation. For further reading see. http://hyperphysics.phy-astr.gsu.edu/hbase/electric/volcon.html#c1
 
okay i understand but my question is in a circuit when we measure a potential at a point A to the mass is it a potential difference or an EMF( if we take an EMF=5V and a resistance and after the resistance the potential is dropped and we have a new potential for exemple equal to 4.25V after the resistance,this potential referred to the mass is it an emf or a potential difference?)
 
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