Water at 43.3°C flows over a large square plate at a velocity of 21 cm/s. The plate is 1.9 m long (in the flow direction) and 1.9 m wide, and itssurface is maintained at a uniform temperature of 10.0°C. Calculate the steady rate of heat transfer per unit width of the plate in watts (W). Theproperties of water at the film temperature of (T + Too)/2 = (10 + 43.3)/2 = 27°C are p = 996.6 kg/m3, k = 0.610 W/m-°C, µ = 0.854 x 10-3 kg/m-s,and Pr = 5.85. (Round the final answer to the nearest whole number.) An incandescent light bulb is an inexpensive but highly inefficient device that converts electrical energy into light. It converts about 10percent of the electrical energy it consumes into light while converting the remaining 90 percent into heat. (A fluorescent light bulb willgive the same amount of light while consuming only one-fourth of the electrical energy, and it will last 10 times longer than anincandescent light bulb.) The glass bulb of the lamp heats up very quickly as a result of absorbing all that heat and dissipating it to thesurroundings by convection and radiation. Consider a 0.525-m-diameter 100-W light bulb cooled by a fan that blows air at 30°C to thebulb at a velocity of 306 m/s. The surrounding surfaces are also at 30°C, and the emissivity of the glass is 0.9. Assuming 10 percent ofthe energy passes through the glass bulb as light with negligible absorption and the rest of the energy is absorbed and dissipated bythe bulb itself, determine the equilibrium temperature of the glass bulb. Assume a surface temperature of 100°C for evaluation of us-The properties of air at 1 atm pressure and the free stream temperature of 30°C are k = 0.02588 W/m°C, v = 1.608x10-5 m2/s, Hoo =1.872x10-5 kg/m.s, Hs at 100°C = 2.181x10-5 kg/m.s, and Pr = 0.7282.ww100 W2 = 0.9Light, 10 W

Reynolds number is calculated for V=.21 m/s. Nusselt number are found and from here H is calculated.…

Water at 43.3°C flows over a large square plate at a velocity of 21 cm/s. The plate is 1.9 m long (in the flow direction) and 1.9 m wide, and its surface is maintained at a uniform temperature of 10.0°C. Calculate the steady rate of heat transfer per unit width of the plate in watts (W). The properties of water at the film temperature of (Ts + Too)/2 = (10 + 43.3)/2 = 27°C are p = 996.6 kg/m³, k = 0.610 W/m-°C, µ = 0.854 × 10-3 kg/m-s, and Pr = 5.85. (Round the final answer to the nearest whole number.)

Water at 43.3°C flows over a large square plate at a velocity of 21 cm/s. The plate is 1.9 m long (in the flow direction) and 1.9 m wide, and its surface is maintained at a uniform temperature of 10.0°C. Calculate the steady rate of heat transfer per unit width of the plate in watts (W). The properties of water at the film temperature of (Ts + Too)/2 = (10 + 43.3)/2 = 27°C are p = 996.6 kg/m³, k = 0.610 W/m-°C, µ = 0.854 × 10-3 kg/m-s, and Pr = 5.85. (Round the final answer to the nearest whole number.)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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