(1) A copper wire 0.8 mm diameter at 150°C is suddenly dipped into water at 35°C. If h=85.5 W/m²K, estimate the time required to cool the wire to 95°C. (ii) If the same wire were placed in air instead of water what would have been the time required to cool it to 95°C. h=11.65 W/m²K For Copper: p= 9000 kg/m³, c = 0.38 kJ/kg K, k = 373 W/mK

(1) A copper wire 0.8 mm diameter at 150°C is suddenly dipped into water at 35°C. If h=85.5 W/m²K, estimate the time required to cool the wire to 95°C. (ii) If the same wire were placed in air instead of water what would have been the time required to cool it to 95°C. h=11.65 W/m²K For Copper: p= 9000 kg/m³, c = 0.38 kJ/kg K, k = 373 W/mK

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.26P

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