On Fri, 07 Mar 2008 13:14:33 -0600, (DT)
wrote:


Do the holes in the prongs of an electric plug serve any purpose? If
so, what is that purpose?
Thanks for any information.


When you plug it in it mates with dimpled tab to make secure contacts.
If in double break apart a receptacle(only couple dollars a piece) and
see for yourself.


The Straight Dope addressed this question, and there seems to be no one simple
answer:

http://www.straightdope.com/classics/a2_389.html

I think it's because putting holes in things make them stronger, like
the guy said. Look at the George Washington Bridge in NYC. It has
loads of holes and look at how strong it is.

Just for the record, I just dismantled two outlets, one inexpensive one and the
other a high end commercial quality Decora... no dimpled tab in either, just
flat copper strips.

I have a related question. Why are some prongs solid, others are
folded over with each layer totally flat against the other, and still
others are foled over but have one side freely attached and springy.

The third kinds seems the best.

But sometimes with the second type, I force the two layers apart so
the plug will stay in the outlet better.

Why don't they make this easier to do?

Will I cut my finger off?