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Matter in Our Surroundings — Science STD 9 — Question

Rajasthan BoardEnglish MediumSTD 9ScienceMatter in Our Surroundings3 Marks
Question
Why is heat energy needed to melt a solid? What is this heat energy called?
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Answer

When a solid is heated, the heat energy makes its particles vibrate more vigorously. At the melting point, the particles of solid have sufficient energy to overcome the strong forces of attraction holding them in fixed positions and break to form small groups of particles. This heat energy is kinetic energy.

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