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Benchmark SC.B.1.2.6 (Assessed As B.1.2.2). The student knows ways that heat can move from one object to another. Radiation. Energy reaches the Earth in the form of radiation (electromagnetic waves) ex. heat and light
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BenchmarkSC.B.1.2.6 (Assessed As B.1.2.2) The student knows ways that heat can move from one object to another.
Radiation • Energy reaches the Earth in the form of radiation (electromagnetic waves) • ex. heat and light • Radiation moves energy without any help from matter. We say the Sun’s energy radiates through space to reach Earth. That means it travels in waves and doesn’t need atoms and molecules to move along. • Heat is the flow of energy from a higher temperature to a lower temperature
Convection • Flow of a heated material (usually gases or liquids); warm air (or liquid) rises because it is less dense and cold air (or liquid) sinks because it is more dense; this causes a convection current. Ex. gases in an oven, pot of boiling water
How Does It Work? When the bottle of warm water is placed on top of the cold water, the more dense cold water stays in the bottom bottle and the less dense warm water is confined to the top bottle. However, when the cold water bottle rests on top of the warm water, the less dense warm water rises to the top bottle and the cold water sinks. The movement of warm and cold water inside the bottles is referred to as the convection current.
Conduction Molecules are heated by direct contact (solid objects transfer heat the best); molecules in hotter objects move more rapidly than those in cooler objects. Ex. metal spoon left in pot
How Does It Work? Water is a great substance for soaking up heat. The thin balloon allows the heat to pass through very quickly and warm the water. As the water closest to the flame heats up, it begins to rise and cooler water replaces it at the bottom of the balloon. This cooler water then soaks up more heat and the process repeats itself. In fact, the exchange of water happens so often that it keeps the balloon from ever popping!