Are lost volts the difference between EMF and terminal potential difference?

In summary, "lost volts" refers to the difference between the EMF (electromotive force) and terminal pd (potential difference) in an electrical source. In some regions, this term is used to describe the voltage drop in a circuit, which is equal to the product of the current and the source's internal resistance.
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homeworkhelpls
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Are lost volts the difference between EMF and terminal pd?
 
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By "lost volts" I'm assuming you mean "voltage drop". Can you post a typical circuit that has generated this question?
 
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berkeman said:
By "lost volts" I'm assuming you mean "voltage drop". Can you post a typical circuit that has generated this question?
Actually its a general question, but the circuit used is say for example a potential divider
 
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Okay, then what are "EMF" and "terminal pd" in the context of your question? The input battery voltage and the output of the 2-resistor voltage divider?
 
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homeworkhelpls said:
Are lost volts the difference between EMF and terminal pd?
Maybe terminology varies regionally, but here in the UK that’s exactly what is meant by ‘lost volts’ for an electrical source.

E.g. a cell’s emf (measured open-circuit) is 1.60V. With some load, the p.d. between the cell’s terminals drops to 1.45V. Then the ‘lost volts’ = 1.60V - 1.45V = 0.15V.

The ‘lost volts’ value is often (especially for teaching and examination purposes here) taken to equal the product of the current through the supply and the supply’s notional internal resistance.
 
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FAQ: Are lost volts the difference between EMF and terminal potential difference?

What is EMF in an electrical circuit?

EMF (Electromotive Force) is the total energy supplied per coulomb of charge by a power source, such as a battery or generator, when no current is flowing. It is the maximum potential difference the source can provide and is measured in volts.

What is terminal potential difference?

Terminal potential difference is the voltage measured across the terminals of a power source when it is delivering current to a load. It is usually less than the EMF due to internal resistance within the power source.

What are "lost volts" in an electrical circuit?

Lost volts refer to the voltage drop that occurs within the power source itself due to its internal resistance. It is the difference between the EMF and the terminal potential difference when current flows through the circuit.

How is the difference between EMF and terminal potential difference calculated?

The difference between EMF and terminal potential difference is calculated by subtracting the terminal potential difference from the EMF. This difference represents the lost volts due to the internal resistance of the power source.

Why is terminal potential difference usually less than EMF?

Terminal potential difference is usually less than EMF because of the internal resistance of the power source. When current flows through this internal resistance, a voltage drop occurs within the source itself, reducing the voltage available at the terminals.

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