Consider steady-state operation of a disk-shaped electronic device of 1.0 cm diameter, 5.0 mm thickness, and thermal conductivity of 20 W/mK that dissipates 5.0 W of electrical power. The electronic device is bonded to a perfectly insulating base on one side and a 20-cm-long brass (k = 100 W/mK) rod of the same diameter on the other side. The device is inserted into a perfectly insulating wall such that half of the brass rod's length is exposed to 20°C air with convective heat transfer coefficient of 120 W/m²K at the rod surface. You may neglect the contact resistance between the device and the brass rod. a. (35 points) Assuming one-dimensional conduction through the assembly, determine the steady-state temperature at the hottest points on the exposed half of the rod. b. (45 points) If the maximum allowable temperature of the electronic device is 90°C, will steady-state operation of the device be possible? c. d. (20 points) A thermocouple is used to measure the temperature of the rod at a point 1.0 cm from the electronic device. What is the expected steady-state temperature reading by the thermocouple? (Extra credit) The perfectly insulating base on one side of the electronic device is replaced by a brass rod of diameter 1.0 cm and length 5.0 cm that is bonded to the electronic device with negligible contact resistance. The electronic device assembly is then inserted into the perfectly insulating wall such that the shorter brass rod is completely embedded in the wall (with 15 cm of the longer brass rod exposed to air). Will steady-state operation of the device be possible? Electronic device Perfectly- insulated Brass rod

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Consider steady-state operation of a disk-shaped electronic device of 1.0 cm diameter, 5.0 mm thickness, and thermal conductivity of 20 W/mK that dissipates 5.0 W of electrical power. The electronic device is bonded to a perfectly insulating base on one side and a 20-cm-long brass (k = 100 W/mK) rod of the same diamete