Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity – McqOptions

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1.	Air enters a rectangular duct measuring 30 cm by 40 cm with a velocity of 8.5 m/s and a temperature of 40 degree Celsius. The flowing air has a thermal conductivity 0.028 W/m K, kinematic viscosity 16.95 * 10¯⁶ m²/s and from empirical correlations the Nusselt number has been approximated to be 425. Find out the flow Reynolds number
A.	1.1719 * 10⁶
B.	2.1719 * 10⁶
C.	0.1719 * 10⁶
D.	4.1719 * 10⁶
Answer» D. 4.1719 * 10⁶

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