An electrical resistor is connected to a battery, as shown schematically. After a brief transient, the resistor assumes a nearly uniform, steady-state temperature of 95°C, while the battery and lead wires remain at the ambient temperature of 25°C. Neglect the electrical resistance of the lead wires.

(a) Consider the resistor as a system about which a control surface is placed and Equation 1.11 c is applied. Determine the corresponding values of Ein (W), Eg (W), Eout (W), and Est (W). If a control surface is placed about the entire system, what are the values of Ein, Eg, Eout, and Est?

(b) If electrical energy is dissipated uniformly within the resistor, which is a cylinder of diameter D = 60 mm and length L = 250 mm, what is the volumetric heat generation rate, q (W/m3)?

(c) Neglecting radiation from the resistor, what is the convection coefficient?

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I = 6A Resistor Battery- Air V = 24 V T= 25°C Lead wire