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The Topic: Electrical Cords


What's the point of the holes at the end of each prong of the electric plug?


  Doc Brown

Take apart an electrical outlet and touch the contact wipers that the prongs slide into. You'll get a nasty shock! But if you'd taken care to disconnect it from the power grid first, you would find that they have have bumps on them. These bumps fit into the holes so that the outlet can grip the plug’s prongs more firmly. This detenting prevents the plug from slipping out of the socket due to the weight of the plug and cord. It also improves the contact between the plug and the outlet, which is an all-around good thing.

Our Lawyers  

The holes also allow manufacturers to 'factory seal' applicances, but placing a tie or lock in the holes, and forcing you to agree to some terms or safety conditions before use, much like you do with most retail software before opening the package.

  CEO Nwabudike Morgan

Also, there is a small but important cost savings in raw materials, in the form of the metal used in the prongs. It's very small, but factored over billions of prongs, every little bit helps the bottom line!

  Doc Brown

Hopefully you didn't try the experiment without reading ahead, and survived to get all three explanations.

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