JEE Mains · Physics · STD 11 - Fluid mechanics
- JEE Mains 2025
- Hard
- MCQ
Water flows in a horizontal pipe whose one end is closed with a valve. The reading of the pressure gauge attached to the pipe is \(P_1\). The reading of the pressure gauge falls to \(P_2\) when the valve is opened. The speed of water flowing in the pipe is proportional to
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Answer & Solution
Correct Answer
(D) \(\sqrt{\mathrm{P}_1-\mathrm{P}_2}\)
Step-by-step Solution
Detailed explanation

Using Bernoulli's theorem
\(\begin{aligned}
& P_1-P_2=\frac{1}{2} \rho v^2 \\
& v \propto \sqrt{P_1-P_2}
\end{aligned}\)
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