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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.
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Solution
- 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.
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Comment upon the following:-
fluidity
