Physics
Emf of a cell is …………… the terminal voltage when cell is not in use, while …………… the terminal voltage when cell is in use.
- greater than, smaller than
- smaller than, greater than
- equal to, greater than
- equal to, smaller than
Current Electricity
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Answer
equal to, greater than
Reason — Emf of a cell is equal to the terminal voltage when cell is not in use and when the current starts to flow in the circuit, then there is a voltage drop due to internal resistance, thus we get, V = E - Ir. Hence, Emf is greater than the terminal voltage when cell is in use.
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