JEE Mains · Physics · STD 11 - 9.1 fluid mechanics
A pressure-pump has a horizontal tube of cross-sectional area \(10\,cm ^{2}\) for the outflow of water at a speed of \(20\,m / s\). The force exerted on the vertical wall just in front of the tube which stops water horizontally flowing out of the tube, is \(...N\) [given : density of water \(=1000\,kg / m ^{3}\) ]
- A \(300\)
- B \(500\)
- C \(250\)
- D \(400\)
Answer & Solution
Correct Answer
(D) \(400\)
Step-by-step Solution
Detailed explanation
\(F =\rho av { }^{2}=10^{3} \times 10 \times 10^{-4} \times 20 \times 20\) \(F =400\)
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