4-115 A 6-cm-high rectangular ice block (k =2.22 W/m-K and a = 0.124 x 10-7 m²/s) initially at –18°C is placed on a table on its square base 4 cm

x 4 cm in size in a room at 18°C. The heat transfer coefficient on the exposed surfaces of the ice block is 12 W/m2-K. Disregarding any heat transfer from the base to the table, determine how long it will be before the ice block starts melting.Where on the ice block will the first liquid droplets appear? Solve this problem using the analytical one-term approximation method.

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