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Circuit Playground: G Is for Ground

2 minutes 52 seconds

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Why do some power cables have two conductors and some have three? Ladyada explains that three prong cables are grounded and provide a layer of safety in electronics. Ladyada and Adabot go through the lab looking for grounded items. Part of the "Circuit Playground" series.

Media Details

Runtime: 2 minutes 52 seconds

Topic: Business, Science
Subtopic: Electricity and Magnetism, Energy, Physics
Grade/Interest Level: 5 - 8
Standards:

Release Year: 2015
Producer/Distributor: Adafruit Industries
Series: Circuit Playground
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Measurement device placed on a circuit powered by three AA batteries. Device shows 0.05 on the display. Caption: (Adabot) zero point zero five amperes.

Person speaking. Illustration of a battery. Caption: A battery uses chemistry to create electricity.

Illustration of a circuit board with a tubular object bridging two paths. Caption: In this circuit, I'm filtering power.

Rectangular diagram with objects moving clockwise around the perimeter. Caption: Electrons flow through the diode in one direction,

Machine labelled DS1052E Digital Oscilloscope with a wavy line across the screen and complex controls. Caption: We measure frequency in units called hertz.

Person in a workshop holding a power cord with three prongs. Caption: The answer is these three-prong cables are grounded.

Person and a robot in a workshop with a laptop in front of them. Caption: Hertz is how many times something happens per second.

Closeup of a complex circuit board with capacitors and other structures. Caption: But ICs, well -- ICs can have lots of connections.

Joules = force x distance. Caption: we multiply force and distance

Person and a robot standing in front of shelves full of boxes. Caption: Kits? What's a kit?

Viewer Comments

Denise P. (Great Falls, MT)

January 28th, 2022 at 03:19 PM

Great video. Helped encourage my students to inquire about the plugs in their home and what that means for each of the devices based on the number of prongs.