JEE Mains · Physics · STD 11 - 9.1 fluid mechanics
Water from a pipe is coming at a rate of \(100\, litres\) per minute. If the radius of the pipe is \(5\, cm\), the Reynolds number for the flow is of the order of : (density of water \(= 1000\, kg/m^3\), coefficient of viscosity of water \(= 1\, mPa\, s\))
- A \(10^3\)
- B \(10^6\)
- C \(10^2\)
- D \(10^4\)
Answer & Solution
Correct Answer
(D) \(10^4\)
Step-by-step Solution
Detailed explanation
Reynolds number\( = \frac{{\rho vd}}{\eta }\) Volume flow rate\( = v \times \pi {r^2}\) \(v = \frac{{100 \times {{10}^{ - 3}}}}{{60}} \times \frac{1}{{\pi \times 25 \times {{10}^{ - 4}}}}\) \(v = \frac{2}{{3\pi }}m/s\) Reynolds number…
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