Closed-circuit Ohm's law & EMF / internal resistance
E = U + Ir — terminal voltage vs load, EMF and internal r.
DC circuitsInstrument reading, resistivity, Ohm’s law, EMF, RC.
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Closed-circuit Ohm's law & EMF / internal resistance
Closed-circuit Ohm's law: I = ε/(R+r) and terminal voltage U = IR.
Closed-circuit Ohm's law with EMF and internal resistance.
Key formulas
I=\mathcal{E}/(R+r)U=IR
How to use
- Tune EMF ε, internal r, and load R.
- Watch the current animation and I/U readouts.
- See how output changes as R approaches r.
Applications
- Closed-circuit Ohm's law & EMF / internal resistance: Closed-circuit Ohm's law with EMF and internal resistance.
- In class, tune parameters for “Closed-circuit Ohm's law & EMF / internal resistance”, then check against the textbook result.
FAQ
When is output power maximized?
In the ideal model, when the load equals the internal resistance (R = r).
What does MVP mean on this page?
An interactive sketch with formulas and parameters. Polished Ready labs are the full bench experience.
What does the “Closed-circuit Ohm's law & EMF / internal resistance” lab practice?
Tune parameters and match readouts to the “Closed-circuit Ohm's law & EMF / internal resistance” relations — useful for prep and demos.
How do I connect meters?
Ammeter in series; voltmeter in parallel — watch polarity and range.