What can be the maximum diameter of the pipe for the water flow of velocity 1 m/s (ν = 10-6) to be laminar in nature? Assume Lower critical Reynolds number to be 2100.

What can be the maximum diameter of the pipe for the water flow of velocity 1 m/s (ν = 10-6) to be laminar in nature? Assume Lower critical Reynolds number to be 2100. Correct Answer 2.1 mm

If the Reynolds number of the flow is below its lower critical Reynolds number, the flow is clearly laminar. The maximum diameter can be found for Re = 2100. The diameter comes out to be 2.1 mm.
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