Question

Give reasons:

We can easily move our hand in air, but to do the same through a solid block of wood, we need a karate expert.

Answer 1

• We can easily move our hand in the air, but to do the same through a solid block of wood, we need a karate expert.
• It is because the molecules of air have less force of attraction between them, and a very small external force can separate them and pass through them.
• However, in solids, the molecules have the maximum force of attraction, and the particles are tightly bound due to this force. Hence, a large amount of external force is required to pass through the solid.