Question

explain why we can easily move our hand in air but to do the same through a plane of wood we need a karate expert .

Answer 1

because of the density of air and solid
solid has height density so we need to exert more force than It

hope it will help u

Answer 2

Air is a gas, it has more space in between particles. But solid block of wood is rigid, hence it is difficult to move our hands through it.