One to ponder over

[ukkid76]

If I had a piece of steel and drilled say a 5mm hole would a 5mm rod fit in the hole or not? Without going in to too much detail about you can never guarantee that a drill or a piece of rod will ever be that accurate just suppose for this experiment that they are 100 percent accurate. Yes or No

[Gef]

If both the hole and the rod were exactly 5mm in diameter then there would be a perfrct fit.

[beenee]

Gef- but they shouldnt be as the hole would have to be just that tiny tiny bit bigger to let the rod past.

On the other hand, the rod would have to be just that tiny tiny bit bigger NOT to fit. So, yes a very good question!

[rja211077]

We are getting into the realms of the concept of infinity here, in particular infinitely small amounts. Basically the rod would have to be an infinitely small amount less in diameter than the hole. The concept of infinity is purely theoretical and therefore, like you say, would never happen in reality. Also there is a matter of thermal expansion. The rod would get bigger with temperature. Daft question. Next.

[mikewith]

rja211077 - I'd say all the above proves this is far from a daft question, but in fact really uqite interesting. Next!

[ukkid76]

All great answers but no one has been bold enough to say either yes or no!!!

[DBusby]

It would fit. I think rja211077 is a bit thick.

[xyzzyplugh]

Unless it got real cold and the hole contracted :-)

[tomr]

Yes.

You didn't ask whether it would be easy.

[Gef]

I thought I had said yes. By the way, temperature is irrelevant as both would contract or expand.

[ukkid76]

A very interesting array of replies but actually a 100 percent accurate 5mm rod (or bar) will not fit in to a 100 percent accurate 5mm hole it is impossible.(or any other sized hole for that matter)

[beenee]

Ok ukkid, I was up until 5am thinking about this one and you're right. If both were exactly the same size, then a micro measure of the rod's outter edge would meet with a micro measure of the hole's inner edge. Very good question! I really enjoyed cracking it :o)

[Gef]

If, as in the original question, the drill is 100% accurate then the piece of metal drilled out will be exactly 5mm and will fit exactly into the 5mm hole!

[gilf]

Temprature is relevant because in heat the rod would expand and the hole would shrink because the metal around the air that is in essence 'The Hole' would also expand therefore close the hole. in cold weater the rod would shrink and 'The hole' become bigger. Its a bit like the old riddle "how much earth in a 10x10x10 hole". The hole is nothing but the metal surrounding the nothing defines how much nothing there is.