Erasing with heat

The video tutorial introduces a Pilot Frixion erasable pen that uses thermochromic ink, which changes color with temperature. The pen's ink can be erased by friction, which generates heat, and can be made to reappear by cooling the ink with a spray can. The tutorial demonstrates how the ink's color can be repeatedly changed by applying heat and cold, making it a useful tool for demonstrating scientific principles related to temperature and color change.

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