Water flows at 0.00027 m3/s through a 10-m long garden hose lying on the ground, with a radius of 0.01 m. Water has a viscosity of 1 mPa.s What is the magnitude of gauge pressure in Pa of the water entering the hose

Respuesta :

Answer:

The gauge pressure is  [tex]P = 687.4 \ Pa[/tex]

Explanation:

From the question we are told that

    The rate of flow is  [tex]Q = 0.00027 m^3 /s[/tex]

      The height is h  =  10 m

      The radius is  r =  0.01 m

     The  viscosity is  [tex]\eta = 1mPa \cdot s = 1 *10^{-3} \ Pa\cdot s[/tex]

       

Generally the gauge pressure according to Poiseuille's equation  is mathematically represented as  

               [tex]P = 8 \pi \eta * \frac{L * v }{ A}[/tex]

Here v is the velocity of the water which is mathematically represented according to continuity equation as

             [tex]v = \frac{Q}{A }[/tex]

Where A is the cross-sectional area which is mathematically represented as

            [tex]A = \pi r^2[/tex]

substituting values

          [tex]A = 3.142 *(0.01)^2[/tex]

           [tex]A = 3.142 *10^{-4} \ m^2[/tex]

So

      [tex]v = \frac{ 0.00027}{3.142*10^{-4}}[/tex]

       [tex]v = 0.8593 \ m/s[/tex]

So

       [tex]P = 8 * 3.142 * 1.0*10^{-3}* \frac{10 * 0.8593 }{ 3.142*10^{-4}}[/tex]

       [tex]P = 687.4 \ Pa[/tex]