Circuit Analysis Concept

Demonstrations in Circuit Analysis

Honeywell portable potentiometer in a wooden case, showing rotary dials, decade selector knobs, and a center-zero galvanometer on the front panel
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Commercial Potentiometer

Students examine commercial potentiometers to see how null-balance techniques enable precise voltage measurement without drawing current from the source. These instruments make voltage division and null detection tangible in a …
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
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Demonstration Potentiometer

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 …
Demonstration Wheatstone bridge on a clear acrylic frame with horizontal slide wire along a centimeter ruler, center-zero galvanometer mounted above, two plug-in resistor positions at top, and an Energizer 6V battery connected below

Slide-Wire Wheatstone Bridge

Students observe how a Wheatstone bridge measures unknown resistance by adjusting a slide wire until the galvanometer nulls. Swapping plug-in resistors of different values shows how bridge sensitivity degrades when …
Wheatstone bridge board with five light bulb sockets in a diamond pattern connected by white conducting strips on brown fiberboard, chalk labels R1 through R4 and Rx, a small knife switch at center, power connections on the sides, mounted on wooden feet. A spare bulb sits on the bench below.
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Light Bulb Wheatstone Bridge

Light bulbs serve as resistive elements in a Wheatstone bridge, making bridge balance and imbalance immediately visible. With four identical bulbs the center indicator stays dark; replacing one 60 W …
Four 60W globe-style incandescent bulbs in ceramic sockets on clear acrylic bases with binding posts. The two on the left glow bright white (parallel), the two on the right glow dim orange (series).
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Series and Parallel Light Bulbs

Identical 60W bulbs wired in series vs. parallel show a dramatic brightness difference, making voltage division and power distribution immediately visible. Use handheld DVMs to measure voltage and current at …
Wooden board with eighteen small incandescent bulbs in sockets wired in series, connected to a DC power supply displaying 30.0 V via red and black leads with alligator clips
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Light Bulbs in Series

Students observe how voltage divides across identical resistors in series and how brightness changes with the number of bulbs. The dramatic dimming when adding bulbs challenges the common misconception that …
Gray Ohm's Law demonstrator panel labeled "OHMS LAW: V=IR" with painted circuit diagram, voltmeter and ammeter, switch, and banana plug connections. Three interchangeable resistance boards displayed alongside: two in parallel, three in parallel, and three in series. A 6V lantern battery is connected with red and black leads.

Series and Parallel Resistors

Demonstrates Ohm's Law and series/parallel resistance rules with direct voltage and current measurements. Interchangeable resistance boards (identical 150-ohm resistors in different configurations) let students predict and verify equivalent resistance for …