The ratio of momentum diffusivity to thermal diffusivity is the ______________ number?
Correct answer: A. Prandtl
- A. Prandtl
- B. Nusselt
- C. Stanton
- D. Grashoff
Explanation
The Prandtl number is the ratio of momentum diffusivity, ν, to thermal diffusivity, α: Pr = ν/α. Nusselt and Stanton numbers involve convection, while Grashof number compares buoyancy with viscous effects.
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