DC Circuits
PIRA classification 5F
Grayed Demos are either not available or haven't been built yet |
Please note that these tables have not yet been edited to match the equipment that is available within the UW-Madison lecture demo lab. There maybe many items listed within these tables that we either "can not do" or have available.
5F10. Ohm's Law
PIRA # |
Demonstration Name |
Subsets |
Abstract |
5F10.05 |
charge density in circuits |
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Two demonstrations: first, an electroscope is used to probe the charge density along a large resistance attached to a 5 KV supply, and second, an example where current is flowing through a resistance with no change in potential. |
5F10.10 |
Ohm's law |
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Measure current and voltage in a simple circuit. Change the voltage or resistance. |
5F10.10 |
Ohm's Law |
pira200 |
An ammeter, voltmeter, rheostat, and battery pack are connected to demonstrate Ohm's law. |
5F10.10 |
Ohm's law |
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A battery, rheostat, and meters in a circuit. |
5F10.10 |
Ohm's law |
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Measure current and voltage in a simple circuit. |
5F10.10 |
Ohm's law |
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Place 2, 4, and 6 V across a resistor and measure the current, then graph. |
5F10.12 |
water analogy circuit |
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A water analogy illustrates voltage drops across a dc circuit. |
5F10.15 |
water Ohm's law analog |
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5F10.15 |
water analog |
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A water analog of Ohm's law. |
5F10.15 |
IR drop in a wire |
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Clip wires from the terminals of flashlight lamps at various points along a stretched wire carrying 2 - 5 amps. |
5F10.20 |
potential drop along a wire |
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Lecture galvanometers configured as a voltmeter and ammeter measure current and voltage on several samples of wire of the same length. A slide clip can be used to vary length. |
5F10.20 |
voltage drop along wire |
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Measure the voltage at six points on a long resistance wire. |
5F10.25 |
potential drop with Wimshurst |
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A 3 m long wood bar is attached at one end to one terminal of a static machine. The other end can be grounded or insulated. Attach several electroscopes along the bar to show flow of charge and potential drop. |
5F10.26 |
high voltage Ohm's law |
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Two ends of a dry stick are attached to a static machine. Measure with an electrostatic voltmeter and microammeter. |
5F15. Power and Energy
5F15.32
PIRA # |
Demonstration Name |
Subsets |
Abstract |
5F15.10 |
electrocalorimeter |
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Determine the power delivered by temperature change in water and compare to that computed from voltage, current, and time. |
5F15.11 |
flow calorimeter |
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Water is heated electrically as it flows through a tube. |
5F15.12 |
heating by current from a static mot |
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The ends of a piece of wood sealed in a glass tube are attached to a static machine. The half watt dissipated heats the air and an attached manometer measures the volume change. |
5F15.15 |
KWH meter and loads |
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Measure the power consumed by an assortment of household appliances. |
5F15.16 |
Nichrome heating with current |
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Vary the lentgh of a long nichrome wire at a fixed voltage. Show the athe nichome wire glows and heats up faster at shorter lentghs. Also point out that it sags as it heats up. |
5F15.17 |
heating wires in series |
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Several lengths of different wires of the same length are soldered together in series and a piece of paper is hung from each by soft wax. As current is passed through the wire, the paper falls off at different times. |
5F15.20 |
hot dog cooker |
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Hook nails to 110V and place them on and then in a hot dog. |
5F15.30 |
fuse with 30v lamp |
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5F15.31 |
fuse-wire problem |
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With fuse wires of different diameters connected in parallel, which will burn out first? |
5F15.32 |
vaporize wire - exploding wire |
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A thin wire or strip of aluminum foil vaporizes when a large capacitor discharges through it. |
5F15.33 |
fuse wire |
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Fuse wire is used with a miniature house circuit. |
5F15.34 |
fuses |
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Fuse wire of different sizes are connected across a heavy copper buss. |
5F15.35 |
fuse with increasing load |
pira200 |
A fuse wire will eventually fail when the load on the circuit is increased. |
5F15.40 |
voltage drops in house wires |
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Two resistance wires substituting for house wiring glow when they power a load of lamps and heaters. |
5F15.45 |
Alternating Copper and Nichrome - I2R losses |
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Alternating Copper and nichrome wires in series show different amounts of heating due to current. The nicrhrome segments glow. 30Vdc at 18 amps |
5F15.50 |
I2R Loss is 4 Different Wires |
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Thick copper, Thin copper, nicrhrome, and nickel wires of the same length are in series and powered with about 3 to 5 Vdc at 3 amp. A galvanometer is use to show the power loss of each segment. |
5F20. Circuit Analysis
PIRA # |
Demonstration Name |
Subsets |
Abstract |
5F20.10 |
Kirchoff's voltage law |
pira200 |
Measure the voltages around a three resistor and battery circuit. |
5F20.13 |
voltage divider |
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A simple series circuit of a battery and two resistors. |
5F20.15 |
continuity of current |
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Same as Eo-4. |
5F20.15 |
continuity of current |
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An ammeter can be inserted into any branch of a circuit to show currents in and out of a node. |
5F20.16 |
conservation of current |
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Measure the currents entering and leaving a node. |
5F20.20 |
superposition of current |
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Same as Eo-7. |
5F20.20 |
superposition of currents |
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Measure the current from one battery, a second in another position, and the combination in a circuit. |
5F20.20 |
superposition |
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Shows a standard superposition circuit. |
5F20.25 |
reciprocity |
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Shows a standard reciprocity circuit. |
5F20.30 |
potentiometer |
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A slide wire potentiometer is used with a battery and demonstration galvanometer. |
5F20.30 |
potentiometer |
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A slide wire potentiometer with a standard cell. |
5F20.31 |
rheostat as potential divider |
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Contrast the slide wire rheostat when used as a rheostat or potential divider. |
5F20.32 |
long potentiometer |
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Use a ten foot length of nichrome wire as a slide wire potentiometer. |
5F20.33 |
rheostat potential divider |
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A rheostat and six volt battery demonstrate a potential divider. |
5F20.40 |
wheatstone bridge - slide wire |
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The slide wire Wheatstone bridge. |
5F20.40 |
wheatstone bridge - slide wire |
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Two nichrome wires are stretched across the lecture bench and sliding clips connected to a galvanometer are used to find equal potential points. |
5F20.41 |
wheatstone bridge - human galvan. |
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Stretch a loop of close line previously soaked in salt solution in a parallelogram and hook the ends to a 110 V line. Touch two points of the same potential without shock. |
5F20.42 |
wheatstone bridge |
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A demonstration Wheatstone bridge with a built in meter and several plug in resistors. |
5F20.45 |
lightbulb wheatstone bridge |
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A Wheatstone bridge configuration with lightbulbs for resistors. |
5F20.45 |
light bulb wheatstone bridge |
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Four light bulbs in a Wheatstone bridge arrangement with light bulb indicator. |
5F20.45 |
light bulb wheatstone bridge |
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A light bulb Wheatstone bridge using 110 ac. |
5F20.45 |
wheatstone bridge |
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Four 60 W lamps in a diamond bridge with a 10 W lamp as the indicator. An additional 6 V lamp can be switched in when the circuit is balanced. |
5F20.45 |
wheatstone bridge |
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Three 110 V lamps and a rheostat make up the diamond of a Wheatstone bridge and a small lamp serves as an indicator. |
5F20.50 |
series and parallel light bulbs |
pira200 |
A light bulb board with switches allows configuration of several combinations of series and parallel lamps. |
5F20.50 |
series and parallel light bulbs |
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A light bulb board with switches allows configuration of several combinations. |
5F20.50 |
parallel and series light bulbs |
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Three similar wattage lamps in series, three in parallel. |
5F20.50 |
series-parallel circuits |
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A series-parallel circuit with three bulbs and six switches can be connected 14 ways. |
5F20.50 |
series/parallel light bulbs |
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Three 110 V lamps are wired in series and three are wired in parallel. |
5F20.51 |
light bulb board - 12 V |
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A board with 12V bulbs and a car battery allow combinations of up to three series or three parallel loads. |
5F20.55 |
series/parallel resistors |
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Measure the current flowing through a wire resistor with 6 V applied and then series and parallel combinations. |
5F20.56 |
wire combinations |
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A wire circuit is arranged so a segment of n length can have 1 or n wires in parallel. Drawing. |
5F20.60 |
equivalent series resistance |
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A series of resistors in a circuit are replaced by a single resistor. |
5F20.61 |
parallel resistance - integral value |
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A formula for obtaining integral values of resistors in parallel to obtain an integral equivalent resistance. |
5F20.61 |
equivalent parallel resistance |
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Parallel resistors are replaced by a single resistor in a circuit. |
5F20.63 |
Thevenin's equivalent resistance |
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A Wheatstone bridge resistance circuit is used to reduce resistor combinations to an equivalent resistance. |
5F20.64 |
equivalent circuit flasher |
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A neon flasher circuit shows the combination rules for series and parallel combinations of resistance and capacitance by timing light flashes. |
5F20.71 |
large circuit boards |
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A modular circuit board made for 500 student auditoriums. |
5F20.72 |
general circuits board |
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A circuit board laid out so meters can be plugged in and readings taken for demonstrations of series-parallel circuits and Kirchhoff's laws. |
5F20.75 |
three-way switch |
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A large circuit board demonstrates a three way switch. |
5F20.79 |
one boar, river, six people |
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An electrical circuit for solving the problem of getting across the river. |
5F20.95 |
equivalent resistance analog comput. |
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Using the equivalent resistance of a circuit as an analog computer for finding the focal length of an optical problem. |
5F30. RC Circuits
PIRA # |
Demonstration Name |
Subsets |
Abstract |
5F30.10 |
capacitor and light bulb |
pira200 |
A 5600 microfarad capacitor, a light bulb, and a 120 V dc supply in series show a long time constant. |
5F30.10 |
capacitor and light bulb |
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A 5600 microF capacitor is charged and discharged through 7.5 and 40 W light bulbs. |
5F30.10 |
long RC time constant |
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A 5600 microF capacitor, a light bulb, and a 120 V dc supply in series show a long time constant where the bulb dims as the capacitor charges. |
5F30.11 |
light the bulb |
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Charge a capacitor with DC and discharge through a light bulb, try the same thing with AC. |
5F30.12 |
discharge a capacitor |
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Discharge a capacitor through a resistor. Read the voltage with a meter. |
5F30.15 |
RC time constant on galvanometer |
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A series RC circuit with a galvanometer. Diagram. |
5F30.16 |
RC voltage follower |
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Use a voltage follower to isolate the circuit from the display. |
5F30.20 |
RC time constant on scope |
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A circuit with a slow time constant (.1 - 10 sec.) is charged and discharged and the current and voltage are displayed on a dual trace storage scope. |
5F30.20 |
RC charging curve |
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Show charging and discharging a RC circuit with a battery on an oscilloscope. |
5F30.21 |
RC time constant |
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Show the time constant from an RC circuit on an oscilloscope. |
5F30.21 |
RC time constant |
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A plug in circuit board for showing RC time constants on the oscilloscope. |
5F30.22 |
time constant of an capacitive cir. |
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The time constant of a RC circuit driven by the calibration signal is shown on an oscilloscope. |
5F30.28 |
finding R from time constant |
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A circuit to measure high resistances by using an RC charging time. |
5F30.50 |
series and parallel capacitors |
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Two 2 microF capacitors in series or parallel with a 40 W lamp. |
5F30.60 |
neon relaxation oscillator |
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5F30.60 |
blinking neon bulb |
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A neon bulb in parallel with a capacitor will light periodically as the capacitor charges and discharges. |
5F30.60 |
RC relaxation oscillator |
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An RC relaxation oscillator has a neon lamp across the capacitor provide a visible discharge. |
5F30.60 |
RC flasher circuit |
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A neon lamp in parallel with the capacitor in a series RC circuit. |
5F30.60 |
flashing neon light |
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A battery powered neon light oscillator. |
5F30.60 |
neon relaxation oscillator |
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A circuit for a neon relaxation oscillation oscillator. Reference: AJP 13(12),415. |
5F30.60 |
relaxation oscillator |
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An RC neon light relaxation oscillator. |
5F30.61 |
relaxation siren oscillator |
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A double RC relaxation oscillator with slow and fast periods gives a siren waveform. |
5F30.68 |
backward and forward waves |
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RC circuits are used to get a wave in neon bulbs that goes from the sink to the source. |
5F30.71 |
capacitance operated relay |
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References but no information on the circuit. Bring your hand close to a aluminum plate and the relay triggers. |
5F30.80 |
fun circuit |
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One box has switches that control two lights in another box but only one wire connects the two boxes. |
5F40. Instruments
PIRA # |
Demonstration Name |
Subsets |
Abstract |
5F40.10 |
sensitivity and resistance of a galv |
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A circuit for the determination of galvanometric constants. |
5F40.10 |
sensitivity and resistance of galvan |
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Use external resistors to measure the resistance and sensitivity of a galvanometer. |
5F40.15 |
voltmeter and electroscope |
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Connect series resistance to a galvanometer to make a voltmeter with low sensitivity and measure several dry batteries in series with both the voltmeter and an electroscope. |
5F40.20 |
converting a galvanometer to a voltm |
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Knowing the resistance and sensitivity of a galvanometer, add a series resistance and check with a voltage. |
5F40.20 |
galvanometer as voltmeter and ammete |
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A galvanometer is used with shunt and series resistors. |
5F40.21 |
loading by a voltmeter |
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Measure the voltage across a high resistance circuit with high and low impedance voltmeters. |
5F40.25 |
converting a galvanometer to a ammet |
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Knowing the resistance and sensitivity of a galvanometer, add a shunt resistance and measure a current. |
5F40.30 |
hot wire ammeter |
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A crude hot wire galvanometer. |
5F40.30 |
hot wire ammeter |
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Diagram of a hot wire ammeter. (E-171). |
5F40.35 |
iron vane meter |
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Repulsion from induced magnetism in two soft iron bars in a solenoid forms the basis of a heavy current ammeter. |
5F40.50 |
multimeters |
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A couple multimeters are pictured. |