A 0.1-W small cylindrical resistor mounted ona lower part of a vertical circuit board is 0.3 in long andhas a diameter of 0.2 in. The view of the resistor is largelyblocked by another circuit board facing it, and the heat transferthrough the connecting wires is negligible. The air is free to flow through the large parallel flow passages between theboards as a result of natural convection currents. If the airtemperature at the vicinity of the resistor is 120°F, determinethe approximate surface temperature of the resistor. Evaluateair properties at a film temperature of 170°F and 1 atm pressure.Is this a good assumption?

A 0.1-W small cylindrical resistor mounted ona lower part of a vertical circuit board is 0.3 in long andhas a diameter of 0.2 in. The view of the resistor is largelyblocked by another circuit board facing it, and the heat transferthrough the connecting wires is negligible. The air is free to flow through the large parallel flow passages between theboards as a result of natural convection currents. If the airtemperature at the vicinity of the resistor is 120°F, determinethe approximate surface temperature of the resistor. Evaluateair properties at a film temperature of 170°F and 1 atm pressure.Is this a good assumption?

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.27P

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