Prandtl number is the reciprocal of
A
$$\frac{{{\text{Thermal diffusivity}}}}{{{\text{Momentum diffusivity}}}}$$
B
Thermal diffusivity × Momentum
C
Thermal diffusivity × Mass diffusivity
D
Mass diffusivity × Momentum diffusivity
Correct Answer: $$\frac{{{\text{Thermal diffusivity}}}}{{{\text{Momentum diffusivity}}}}$$