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5F20.50 - Series and Parallel Resistance with Bulbs (Gray's Lights)

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​5F20.50 - Series and Parallel Resistance with Bulbs (Gray's Lights)

Title5F20.50 - Series and Parallel Resistance with Bulbs (Gray's Lights)

Demonstrate how light bulbs (resistors) behave in series and in parallel.

Assembly Instructions

Obtain equipment for "Gray's Lights" demo. Screw in the threaded brass rods into the wooden base and connect each one to an electrode of the black power supply using banana cables and momentary contact switch. The black power supply should be set to 12V.  Plug in the power supply to the cart, and the cart into the wall or bench outlet.

Setup Time15
Operation Time
Preview Time5
Operation Instructions

Connect lightbulbs in various arrangements. Turn on power supply, and press down on the momentary contact switch to give power to the circuit.

Typically we show lightbulbs in series, parallel, series and parallel, and a lightbulb connected to the same rod. Each variation will show different brightness in the bulbs.

Demonstrators can make different combinations of the light bulbs to show either series, parallel, or mixed circuits, by the variation in brightness of the light bulbs.

Demo on DimeNo
PIRA 200Yes
Export Instructions (if different)

​Light bulbs are used as resistors in the demonstration of series and parallel circuits. Their brightness depends on the current flowing through them which varies with their arrangement.

Category5 Electricity and Magnetism
Subcategory5F - DC Circuits
KeywordsGray's lights, Gray's lites
Construction Information
light bulb on clip - 12V
mounting frame with support wires
banana cable
momentary contact switch
power supply - 25V, 30A (small, black)