<p>The reading of pressure metre attached with a closed pipe is&nbsp;<span class="equation">\(4.5 \times 10^4N/m^2\)</span>. On opening the valve, water starts flowing and the reading of pressure metre falls to&nbsp;<span class="equation">\(2.0\times10^4N/m^2\)</span>.&nbsp;The velocity of water is found to be&nbsp;<span class="equation">\(\sqrt{V}\)</span>m/s. The value of V is____</p>