A hot dog can be considered to be a 12 centimeter long cylinder,whose diameter is 2 cm and whose properties are ? = 980 kg/m3 , cp= 3.9 kJ/kg · K, k = 1.2 W/m · K, and ? = 2 × 10?7 m2 /s. A hot doginitially at 5?C is dropped into boiling water at 100?C. The heattransfer coefficient at the surface of the hot dog is estimated tobe 600 W/m2 · K and the hot dog can be considered cooked when itscenter temperature reaches 80?C (a) Determine how long it will taketo cook considering the hot dog as a long cylinder. (b) Determinethe cooking time assuming lumped capacitance.
