Question

. The Reynolds number Re is a dimensionless group of variables that plays an important role in fluid mechanics. It presents the ratio of the inertial and viscous forces in

a fluid, and it is defined as: R e=\frac{v D}{v}, \text { where } v=\text { velocity }, D=\text { characteristic linear dimension of system , and } v=\text { kinematic viscosity. Evaluate Re for air }\left(v=15 \times 10^{-6} \mathrm{~m}^{2} / \mathrm{s} \text { ), if } v=10 \mathrm{~m} / \mathrm{s} \text { and } \mathrm{D}=1 \mathrm{~m},\right. \text { in } both Sl and English units. (15 points)

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