A circular plate of diameter (0.74 m) is placed some how 1.5 mețer above the room floor, if the Raleigh number can be approximated by Ra= 7.653E7 D and temperature difference between surface and room air temperature is 73 C, air properties: k= 0.0372 W/m.K, Pr= 0.686. WVhat is the initial rate of cooling by convection (kJ/s) from the Lower surface ONLY (Watts)? Select one: O A. 148.40 O B. 45.93 O C. 297.52 O D. 219.07 O E 70.67

A circular plate of diameter (0.74 m) is placed some how 1.5 mețer above the room floor, if the Raleigh number can be approximated by Ra= 7.653E7 D and temperature difference between surface and room air temperature is 73 C, air properties: k= 0.0372 W/m.K, Pr= 0.686. WVhat is the initial rate of cooling by convection (kJ/s) from the Lower surface ONLY (Watts)? Select one: O A. 148.40 O B. 45.93 O C. 297.52 O D. 219.07 O E 70.67

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 5.31P

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