Heat

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Heat is the total kinetic and potential energy of molecules in a substance that flows from hot to cold regions. Temperature is the degree of hotness or coolness measured in a specific unit. Heat is en…

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1. EXPANSION: When heated, substances expand as molecules vibrate faster and move apart. Example: Railway tracks have gaps to prevent buckling in summer heat. 2. CHANGE OF STATE: Solids become liquids…

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This is CONDUCTION. In solids, molecules are tightly packed and cannot move freely. When the spoon's end (in hot tea) is heated, its molecules vibrate faster and collide with neighboring molecules, tr…

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Wool keeps us warm because of CONDUCTION prevention and air trapping. Wool fibers trap small pockets of air between them. Air is an excellent insulator (bad conductor of heat) and prevents body heat f…

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This demonstrates the THERMAL CONDUCTIVITY of different metals. Copper conducts heat fastest (match falls first), followed by aluminum, then brass, and finally iron. This ranking shows that copper is …

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When potassium permanganate crystals are heated at the bottom of water, purple streaks rise upward and spread outward. This demonstrates CONVECTION. Hot water at the bottom becomes less dense (molecul…

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Hot air balloons work through CONVECTION principles: 1) A heat source (burner) inside the balloon heats air molecules. 2) Heated air becomes less dense and rises inside the balloon. 3) As warm air acc…

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SEA BREEZE (day time): Land heats faster than water. Hot air above land becomes less dense and rises, creating low pressure. Cool air from the sea moves toward land to replace it, creating a breeze fr…