A nail becomes warm when it is hammered into a plank. Explain why ?

What do you feel when you thouch a nail immediately after it is hammered into a wooden plank?Why?

Nitric oxide becomes brown when released in air. Explain why ?

Ordinary paper becomes transparent when it is oiled. Explain why.

Answer the following question in one sentence : A metal can be hammered into a thin sheet. Explain why

Why does a saw become warm when it is used to cut a log of wood ? State the energy transformation taking place.

When an iron nail is hammered, it becomes hot. Why?