Electronics · DC circuits / Principles and inquiry
Voltage divider and potentiometer experiment guide
Adjust the potentiometer position to control the output voltage. Find out why connecting a load changes it.
How does it work?
Without a load, Vout = αVin. Connecting a load lowers the output voltage.
Key relationship
R₂ = αR · Vout = Vin(R₂ ∥ RL)/(R₁ + R₂ ∥ RL)
Try this investigation
- Move the wiper and read the output voltage before and after connecting the load.
- Run and record each of the three baseline presets.
- At 50%, connect a load and change only its resistance.
Interpreting your results
What is the output with 6 V input, a 50% wiper position and a 10 kΩ load?
2.4 V
Assumptions and limitations
The ideal potentiometer has a total resistance of 10 kΩ. Position is limited to 5–95% to avoid a short at the endpoints. The voltmeter has infinite resistance. Use this simulation; do not reproduce it with real power supplies or wall outlets.