Heat may be transported from one point to another by any of three possible mechanisms conduction, convection, and radiation. We study the rate of energy transfer between bodies due to temperature difference between them.
`text(Convection :)`
Convection is the process in which heat is carried from place to place by the bulk movement of a fluid. In liquid and gases, the atoms or molecules can move from point to point. The transfer of heat that accompanies mass transport is called convection.
In forced convection, a fan or pump sets up fluid currents. For examples, a fan blows air, or a pump circulates water in a hot-water heating system in a house.
In free convection, it occurs because the density of a fluid varies with its temperature.
An example of convection currents in a pan of water being heated on a gas burner. The currents distribute the heat from the burning gas to all parts of the water. The direction of convection current is opposite to acceleration due to gravity as shown in figure.
`text(Conduction :)`
Transfer of energy due to vibration and collision of medium particles without dislocation from their equilibrium position.
Conduction is the mechanism of transfer of heat between two adjacent parts of a body because of their temperature difference. Suppose one end of a metallic rod is put in a flame, the other end of the rod will soon be so hot that you cannot hold it by your bare hands.
`text(Radiation :)`
Radiation is the process in which energy is transferred by means of electromagnetic waves.
All bodies continuously radiate energy in the form of electromagnetic waves. It does not require a material medium. Electromagnetic waves from the sun, for example, travel through the void of space during their journey to earth.
Even an ice cube radiates energy, although so little of it is in the form of visible light that an ice cube cannot be seen in the dark. The surface of an object plays a significant role in determining how much radiant energy the object will absorb or emit.
Heat may be transported from one point to another by any of three possible mechanisms conduction, convection, and radiation. We study the rate of energy transfer between bodies due to temperature difference between them.
`text(Convection :)`
Convection is the process in which heat is carried from place to place by the bulk movement of a fluid. In liquid and gases, the atoms or molecules can move from point to point. The transfer of heat that accompanies mass transport is called convection.
In forced convection, a fan or pump sets up fluid currents. For examples, a fan blows air, or a pump circulates water in a hot-water heating system in a house.
In free convection, it occurs because the density of a fluid varies with its temperature.
An example of convection currents in a pan of water being heated on a gas burner. The currents distribute the heat from the burning gas to all parts of the water. The direction of convection current is opposite to acceleration due to gravity as shown in figure.
`text(Conduction :)`
Transfer of energy due to vibration and collision of medium particles without dislocation from their equilibrium position.
Conduction is the mechanism of transfer of heat between two adjacent parts of a body because of their temperature difference. Suppose one end of a metallic rod is put in a flame, the other end of the rod will soon be so hot that you cannot hold it by your bare hands.
`text(Radiation :)`
Radiation is the process in which energy is transferred by means of electromagnetic waves.
All bodies continuously radiate energy in the form of electromagnetic waves. It does not require a material medium. Electromagnetic waves from the sun, for example, travel through the void of space during their journey to earth.
Even an ice cube radiates energy, although so little of it is in the form of visible light that an ice cube cannot be seen in the dark. The surface of an object plays a significant role in determining how much radiant energy the object will absorb or emit.