Heat is a form of energy. Heat energy can be transfered from one place to another. Now , we talk about the mechaniisms of transfer of heat by conduction method. Conduction is one of the mechanisms of heat transfer. This takes place usually in solids. When ther exists temperature difference betwwen two points in solid, transfer of heat akes place from the point at high temperature to the point at low temperature without transferring the mass. This kind of transfer heat without transfer of mass is called heat conduction.
Heat conduction in solids can be explained the basis of kinetic theory of matter.A solid is made of a number of atoms which are fixed at lattice sites and are capable of vibrating about their mean positions.the amplitude of vibration of yhese atoms increases with the increase of temperature of solid.
Suppose that one end of a solid of bar is heated. The temperature if that end increases and the atoms in that region to vibrate with higher amplitudes due ro gain of thermal of heat energy. As a result, they collide with neighbouring atoms in cooler region . During such collision hot atoms transfer thermal energy to tje cold atoms and these atom also will begin to vibrate with higher amplitude. In turn, these neighbouring atoms collide with nextneighbouring vold atoms and so on. Thus, there will be continous transfer of heat thermal of thermal energy towards cold end. Here,heat is transfered from one atom to the other while each atom remaons vibrating about their original positions.
In matals there are many free electrons. The electrions are very small and can travel rapidly. When a bmetal is heated,their vibration increase and the energy is passed on to pther atoms and also the numerous electrons in the metal. The electrons rapidly transfer energy by collision to other electrons and other atoms. Hence the transfer of energy n metals is rapid.In non-metallic solids,there are very few free electrions.Here the only way that hewat can transfer through the solids is by direct transfer of energy from one atom another.Hence,yhe the transfer process slow.
Heat conduction in solids can be explained the basis of kinetic theory of matter.A solid is made of a number of atoms which are fixed at lattice sites and are capable of vibrating about their mean positions.the amplitude of vibration of yhese atoms increases with the increase of temperature of solid.
Suppose that one end of a solid of bar is heated. The temperature if that end increases and the atoms in that region to vibrate with higher amplitudes due ro gain of thermal of heat energy. As a result, they collide with neighbouring atoms in cooler region . During such collision hot atoms transfer thermal energy to tje cold atoms and these atom also will begin to vibrate with higher amplitude. In turn, these neighbouring atoms collide with nextneighbouring vold atoms and so on. Thus, there will be continous transfer of heat thermal of thermal energy towards cold end. Here,heat is transfered from one atom to the other while each atom remaons vibrating about their original positions.
In matals there are many free electrons. The electrions are very small and can travel rapidly. When a bmetal is heated,their vibration increase and the energy is passed on to pther atoms and also the numerous electrons in the metal. The electrons rapidly transfer energy by collision to other electrons and other atoms. Hence the transfer of energy n metals is rapid.In non-metallic solids,there are very few free electrions.Here the only way that hewat can transfer through the solids is by direct transfer of energy from one atom another.Hence,yhe the transfer process slow.
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