Question

How can we easily move our hand in a year but to do the same through a solid block of food we need a karate expert. explain?

Answer 1

Because in water the force between the particles is very less than the force in solid and yes a karrate expert has been trained for this

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.