Evaluating Internal Resistance in Circuits (Grade 12 NSC Matric Physical Sciences): Flashcards

Small resistance inside real batteries opposing current flow

$r$

Max potential difference when no current flows

$\varepsilon = V + Ir$

$P = I^2r$

EMF is always ≥ terminal voltage

Series resistor with the EMF source

Greater voltage drop across internal resistance

Measures unknown resistance precisely

$R_x = \frac{R_2 \times R_3}{R_1}$