Terminal PD vs EMF: When is PD Greater?

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The terminal potential difference (pd) of a cell exceeds the electromotive force (emf) when the cell is charging. The emf represents the pd across the cell's terminals with no current drawn, while terminal voltage is the pd when current is flowing. During charging, terminal voltage is calculated as V=E+Ir, where E is the emf, I is the current, and r is the internal resistance. Conversely, when not charging, terminal voltage is V=E-Ir. Understanding these relationships is crucial for analyzing battery performance in different states.
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when is terminal pd greater than emf ?
 
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You need to explain your terms and circumstances more thoroughly.
 
Terminal pd of a cell exceeds the emf when the cell is charging.
 
Hi, EMF of a cell is the pd across its terminals when no current is drawn from it. Terminal voltage is the PD across a cell when a current is drawn from it. When the circuit drawn current e.m.f is larger than terminal voltage. During charging terminal voltage lags behind the e.m.f.
 
Terminal voltage V=E-Ir , when nod charging. Where,E:EMF of the cell. I:current. r:internal resistance of the cell.
Terminal voltage,V=E+Ir , when charging.
 
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