Question

How do you know there is friction when a saw cuts through wood? plz answer it!​

Answer 1

$\huge \mathfrak\blue{Answer}$

Friction is forces which oppose the motion of a body, the rougher the surface, the more the friction. The saw has a smooth surface whereas the wood has a rough surface that creates the friction. When the saw cuts the wood, sparks of fire are also seen. This is due to friction