State Fourier's law of 'conduction and Stefan Boltzmann law of radiation. Express mathematically.

State Fourier's law of 'conduction and Stefan Boltzmann law of radiation. Express mathematically.
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Answer :

Fourier law of heat conduction- It state that ‘for homogeneous material, the rate heat transfer

in steady state in any direction is linearly proportional to temperature gradient in that direction.

Q α dt/dx

Q =-k dt/dx

Stefan Boltzman Law- Stefan concluded from experimental data that‟ total radiation by block

body par unit area per unit time is proportional to fourth power of absolute temperature of the

body.

E α T4 E= σT4

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