Question

Estimate the Reynolds number for a human swimming in water. Approximate the human as a sphere of radius 0.50.5m, swimming at a speed of about 11m/s. The density of water is approximately 1000\text{kg/m}^31000kg/m ​3 ​​ and its viscosity is 0.001\text{N/m}^2\cdot\text{s}0.001N/m ​2 ​​ ⋅s.

Answer 1

Answer:

Re= 5*10^5

Step-by-step explanation:

The numbers are not totally clear as they repeat each other. Under this consideration I will assume the closest values according to the advertised.

r=0.5m

V=1m/s (or) V=11m/s

$\rho = 1000kg/m^3 \\\upsilon = 0.001N/m^2s$

We know that Reynolds number is given by,

$Re=\frac{\rho \upsilon r}{\upsilon}\\Re= \frac{1000*1*0.5}{0.001}\\Re= 5*10^5$

Or for the another velocity

$Re=\frac{1000*11*0.5}{0.001}\\Re= 5.5*10^{6}$