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This article provides an overview of the different methods of transferring thermal energy: conduction, convection, and radiation. It explains how these processes occur in solids, liquids, and gases, and discusses the roles of metals and fluids in conducting heat. The article also explores the concept of specific heat and includes practice problems to test understanding.
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13.2 Transferring Thermal Energy Transfer of Energy Conduction-transfer of energy by direct contact. Faster moving particles of one substance come into contact with slower moving molecules of another substance.
Conduction can take place in solids, liquids, & gases. It is more likely to take place in solids Metals are especially good conductors. Convection-transfer of energy in a fluid by the movement of the heated particles. Any material that can flow is considered a fluid. 2. Heated particles collide with each other and transfer their energy. 3. As particles move faster, they tend to be farther apart.
Offshore convection currents Convection currents form by fluids heating up, rising, cooling off, falling.
Insulators- materials that slows heat flow. Metals are typically poor insulators. 2. Gases are very good insulators. 3. Some types of insulators use pockets of air to help keep heat from flowing.
Specific Heat Specific Heat-the amount of heat that is needed to raise the temp. of 1kg of some material by 1°C (or 1K). Specific heat is measured in J/kg·K OR J/g·ºC Table 1 pg. 432 Water is a good coolant because it has a high specific heat.
Specific Heat Problem 1 How much energy must be transferred as heat to the 420 kg of water in a bathtub in order to raise the water’s temperature from 250C to 370C?
Specific Heat Problem 2 Identify an unknown substance with a mass of 0.455 kg that absorbs 6.33 x 103J, in which a temperature change of 15.50C is observed?