Q. A hole is made at the bottom of the tank filled with water (density $ \text{1000}\,\text{kg/}{{\text{m}}^{\text{3}}} $ ). If the total pressure at the bottom of the tank is 3 atmosphere (1 atmosphere $ \text{=1}{{\text{0}}^{\text{5}}}\,\text{N/}{{\text{m}}^{\text{2}}} $ ), then the velocity of efflux is
Jharkhand CECEJharkhand CECE 2010
Solution:
Applying Bernoullis theorem
$ {{p}_{1}}+0+\rho gH={{p}_{2}}+\frac{1}{2}\rho {{v}^{2}}+\rho gH $
$ {{p}_{1}}-{{p}_{2}}=\frac{1}{2}\rho {{v}^{2}} $
$ 3\times {{10}^{5}}-1\times {{10}^{5}}=\frac{1}{2}\rho {{v}^{2}} $
$ 2\times {{10}^{5}}=\frac{1}{2}\rho {{v}^{2}} $
$ 2\times {{10}^{5}}=\frac{1}{2}\times {{10}^{3}}\times {{v}^{2}} $
$ {{v}^{2}}=400 $
$ v=\sqrt{400} $
