Demonstration Potentiometer - Physics Demonstrations - Demonstration Potentiometer | Physics Undergraduate Labs

Verify all polarities are correct before applying power. Reversed polarity on the standard cell or unknown cell will prevent proper null detection and may damage sensitive cells.

Purpose

Students observe the potentiometer method for measuring unknown voltages by null-balance comparison against a standard cell. A projected galvanometer shows the class how precision voltage measurement works without drawing current from the source.

Demonstration potentiometer on lecture bench with slide wire along a ruler scale, center galvanometer, resistance box, standard cell, 6V battery, and projection meter displayed on the wall above

Figure 1:

Safety Warnings

Warning: Electrical Connection Check

Purpose