If p is the density and $\eta$ is coefficient of viscosity of fluid which flows with a speed v in the pipe of diameter d, the correct formula for Reynolds number Re is :
Solution
<p>The Reynolds number (Re) is a dimensionless quantity used in fluid mechanics to predict the onset of turbulence. It is defined as:</p>
<p>$Re = \frac{{\rho v d}}{{\eta}}$</p>
<p>where:</p>
<ul>
<li>$\rho$ is the fluid density</li>
<li>$v$ is the fluid velocity</li>
<li>$d$ is a characteristic linear dimension (for a pipe, this is typically the diameter)</li>
<li>$\eta$ is the dynamic viscosity of the fluid</li>
</ul>
<p>So, Option C is the correct answer:</p>
<p>${R_e} = {{\rho vd} \over \eta }$</p>
About this question
Subject: Physics · Chapter: Properties of Solids and Liquids · Topic: Elasticity
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