A water tank kept on the ground has an orifice of 2 mm diameter on the vertical side. What is the minimum height of the water above the orifice for which the output flow of water is found to be turbulent? (Assume, g=10 m / s 2, ρ text water =103 kg / m 3 viscosity = 1 centi-poise )

Question

A water tank kept on the ground has an orifice of 2 mm diameter on the vertical side. What is the minimum height of the water above the orifice for which the output flow of water is found to be turbulent? (Assume, g=10 m / s 2, ρ text water =103 kg / m 3 viscosity = 1 centi-poise ) (A) 3 cm (B) 4 cm (C) 6 cm (D) 2 cm

Tardigrade Admin · Accepted Answer

Here, D=2 mm , η=1 centi-poise =10-3 Pa - s and density of the water, ρ=103 kg / m 3 For flow to be just turbulent, Re=3000 ∴ v=(Re η/ρ D)=(3000 × 10-3/103 × 2 × 10-3)=1.5 We know that the velocity head, h=(v2/2 g) ⇒ h=((1.5)2/2 × 10)=0.1125 ≃ 11 cm

Q. A water tank kept on the ground has an orifice of 2mm diameter on the vertical side. What is the minimum height of the water above the orifice for which the output flow of water is found to be turbulent? (Assume, g=10m/s2,ρwater ​=103kg/m3 viscosity = 1 centi-poise )

3 cm

4 cm

6 cm

2 cm

Here, D=2mm,η=1 centi-poise =10−3Pa−s and density of the water, ρ=103kg/m3 For flow to be just turbulent, Re​=3000 ∴v=ρDRe​η​=103×2×10−33000×10−3​=1.5 We know that the velocity head, h=2gv2​ ⇒h=2×10(1.5)2​=0.1125≃11cm

Q. A water tank kept on the ground has an orifice of $2 mm$ diameter on the vertical side. What is the minimum height of the water above the orifice for which the output flow of water is found to be turbulent? (Assume, $g = 10 m / s^{2}, ρ_{water} = 1 0^{3} k g / m^{3}$ viscosity = 1 centi-poise )