Energy: Conduction and Convection
Energy: Conduction and Convection
Energy: Conduction
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Conduction is the process of heat transfer from one particle of a substance to another without any flow of the material medium.
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It is a method of energy transfer that takes place mainly in solids due to the vibration of their particles.
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When a substance is heated, its particles start to vibrate more and more. This vibration is passed onto the neighbouring particles, thus transferring heat energy. This is known as conduction.
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The rate of conduction depends on the material and its state of matter. Metals are typically good conductors of heat because they contain free electrons that can transfer energy quickly throughout the material.
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Insulators are poor conductors of heat. They trap air (which is a poor conductor of heat) within them, reducing the overall rate of heat conduction. Examples include wood, plastic, and foam.
Energy: Convection
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Convection is the process of heat transfer from one point in a fluid (liquid or gas) to another through the actual motion of the fluid itself.
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Convection occurs when a fluid is heated, becomes less dense, and rises. This rising warm fluid is replaced by cooler, denser fluid, which is then heated and also rises. This creates a convection current, which enables energy to be transferred through the fluid.
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Convection is responsible for the transfer of heat in liquids and gases. This is different from conduction, which is most effective in solids.
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Convection currents are responsible for a lot of natural phenomena, like wind patterns and ocean currents. They are also used in home heating systems and cooking appliances.
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Both convection and conduction cause energy transfers, but through different processes and in different types of media. Being aware of where each happens and why is crucial to understanding heat transfer.