Question

what is heat?what are conversion,conviction and radiation?

Answer 1

Heat transfer is the exchange of thermal energy between physical systems. The rate of heat transfer is dependent on the temperatures of the systems and the properties of the intervening medium through which the heat is transferred. The three fundamental modes of heat transfer are conduction, convection andradiation. Heat transfer, the flow of energy in the form of heat, is a process by which a system's internal energy is changed, hence is of vital use in applications of the First Law of Thermodynamics. Conduction is also known as diffusion, not to be confused with diffusion related to the mixing of constituents of a fluid.

Answer 2

Hi friend,

Heat is the for of energy which give  sensation of warmness.
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heat can neither be created nor be destroyed we can only transfer it with 3 ways 1) conduction
          2)convection
          3) Radiation
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Conduction- It is a mode of transfer of heat from one part of the body to another ,from particle to particle in the direction of fall of temperature without  any actual  movement  of the heated particles .
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Convection-It is a mode of transfer of heat from one part of the medium to another part by the actual movement of the heated particles of the medium.
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Radiation- Radiation is a mode of transfer of heat from the source to the receiver without any actual movement of source or receiver and also without heating the intervening medium 
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