The thermal diffusivities for gases are generally
A. More than those for liquids
B. Less than those for liquids
C. More than those for solids
D. Dependent on the viscosity
Answer: Option A
Solution(By Examveda Team)
The thermal diffusivities for gases are generally More than those for liquidsthe thermal conductivity of the liquid is more the gases thermal diffusivity also depends on density and heat capacity. Which is very small in terms of gases. That's why air has low thermal conductivity but relatively high thermal diffusivity that is 0.19 and water has 0.014.
This Question Belongs to Mechanical Engineering >> Heat And Mass Transfer
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