A solid cylindrical needle of diameter d , length L , and densityρ n may fl oat in liquid of surface tension Y . Neglectbuoyancy and assume a contact angle of 0 ° . Derive a formulafor the maximum diameter d max able to fl oat in theliquid. Calculate d max for a steel needle (SG = 7.84) inwater at 20 ° C.

A solid cylindrical needle of diameter d , length L , and densityρ n may fl oat in liquid of surface tension Y . Neglectbuoyancy and assume a contact angle of 0 ° . Derive a formulafor the maximum diameter d max able to fl oat in theliquid. Calculate d max for a steel needle (SG = 7.84) inwater at 20 ° C.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.5P: Evaluate the dimensionless groups hcD/k,UD/, and cp/k for water, n-butyl alcohol, mercury, hydrogen,...

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