physical or chemical change?

at first i thought this was a no brainer but when you hammer a nail into wood i figured it was a physical change but the paranoid side is figuring something quite different

There are some nails which are coated with an adhesive that is activated by the friction of being driven into the wood.

Other than that, I doubt there is anything other than simple physical forces at work, i.e., the nail is simply petenetrating between the cellulose fibers of the wood and is held in place by friction.

Or did I misunderstand your question?

I think the question is, if cellulose fibers are being broken as the nail is driven, are chemical bonds broken in the process? If so, does that qualify as a chemical change? I don’t know the answer, sorry.

Chemical changes may well ensue after the nail is driven into the wood, for example, the nail may rust due to the water content of the wood (even ‘dry’ wood contains a fair amount of water) or it may react with substances in the wood (iron nails driven into oak result in black staining due to a reaction between the iron and tannin I think)

Nope. In simply hammering in an iron nail, you’re breaking some kind of bond, I guess, on the order of a hydrogen bond, but you’re not changing the chemical composition of the wood (Unless you have a really, REALLY big hammer you’re swinging hard enough that the energy melts the nail and burns the wood). You’re just forcing your way between the layers of cellulose.