If a small piece of tin, lying on a wooden stand, is heated to the melting point, and then allowed to cool quietly, then the tin will contract into a ball. Explain the reason for this phenomenon.
If you heat a piece of tin to its melting point and then allow it to cool, it contracts into a ball, because the forces of attraction between molecules of liquid tin are greater than the forces of attraction between molecules of liquid tin and wood, and tin does not wet the wood.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.