Electromotive force and internal resistance
What Electromotive force and internal resistance means in Physics A-Level, as defined for AQA, OCR.
Definitions of Electromotive force and internal resistance
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Reference: OCR
A real source of e.m.f. has internal resistance r, so some energy per unit charge is dissipated inside the source.
A cell has emf ε and internal resistance r, so the terminal pd V equals ε minus Ir.
Topics that use Electromotive force and internal resistance
- Electromotive force and internal resistance (AQA A-Level)
- Internal resistance (OCR A-Level)
Related terms
- Terminal potential difference
- Energy transfer per unit charge in a source
- Lost volts
- Terminal potential difference and lost volts
- Circuit equations and algebraic rearrangement
- Electromotive force
- Experimental uncertainty and improvement
- Graphical analysis of linear relationships
Using Electromotive force and internal resistance in the exam
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