A cylindrical resistor element on a circuit board dissipates 0.15 W of power in an environment at 40C. The resistor is 1.2 cm long, and has a diameter of 0.3 cm. Assuming heat to be transferred uniformly from all surfaces, determine (a) the amount of heat this resistor dissipates during a 24-h period; (b) the heat flux on the surface of the resistor, in W/m2; and (c) the surface temperature of the resistor for a combined convection and radiation heat transfer coefficient of 9 W/m2C. 2. Two 5-cm-diameter, 15-cm-long aluminum bars (k = 176 W/mC) with ground surfaces are pressed against each other with a pressure of 20 atm. The bars are enclosed in an insulation sleeve and, thus, heat transfer from the lateral surface is negligible. If the top and bottom surfaces of the two bar system are maintained at temperatures of 150C and 20C, respectively, determine (a) the rate of heat transfer along the cylinders under steady state conditions and (b) the temperature drop at the interface