Question 9

A tank with a small hole at the bottom has been filled with water and kerosene (specific gravity 0.8). The height of water is 3 m and that of kerosene is 2 m. When the hole is opened, the velocity of fluid coming out from it is nearly: (take g = 10 ms$$^{-2}$$ and density of water = $$10^3$$ kg m$$^{-3}$$)

Pressure from Kerosene ($$P_k$$): $$\rho_k g h_k = (0.8 \times 10^3) \times 10 \times 2 = 16,000\text{ Pa}$$

Pressure from Water ($$P_w$$): $$\rho_w g h_w = 10^3 \times 10 \times 3 = 30,000\text{ Pa}$$

Total Gauge Pressure: $$P_{total} = 16,000 + 30,000 = 46,000\text{ Pa}$$

$$P_{total} = \frac{1}{2} \rho_w v^2$$

$$46,000 = \frac{1}{2} \times 1000 \times v^2$$

$$v = \sqrt{92} \approx 9.59\text{ m/s}$$

Create a FREE account and get:

Download resources