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Can the potential difference across a battery be greater than its emf?

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प्रश्न

Can the potential difference across a battery be greater than its emf?

लघु उत्तरीय
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उत्तर

The potential difference across a battery can be greater than its emf. When the battery is being charged. Basically, emf is the maximum potential difference between the terminals of a battery when the terminals are not connected externally to an electric circuit. Current flows in the closed circuit when the same battery is connected to an electric circuit. When current flows, the potential difference across the terminals of the battery is decreased as some potential drop due to its internal resistance.

Due to the internal resistance in the battery, the potential difference across it is less than its emf. However, for an ideal battery, potential difference and emf are equal.

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अध्याय 32: Electric Current in Conductors - Short Answers [पृष्ठ १९६]

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एचसी वर्मा Concepts of Physics Volume 1 and 2 [English]
अध्याय 32 Electric Current in Conductors
Short Answers | Q 17 | पृष्ठ १९६

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