Questions on Heat transfer

Q1) What is the difference between diffusion & radiation heat transfer?

Q2) Will the thermal resistance of a rectangular slab be increased or decreased if:

  1. the thermal conductivity is increased ?

  2. the cross sectional area is increased ?

  3. the thickness of the slab is increased ?

Q3) State the condition which must be satisfied to treat the temperature distribution in a fin as one-dimensional.

Q4) What do you understand by a lumped system?

Q5) What do you understand by stability criterion for the solution of transient problems?

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