One kilogram of chilled water at 32°F (0°C) is placed in a freezer which is kept at 0°F (?18°C). Approximately how much electric energy (in kilocalories) is needed to operate the compressor to cool this water to 0°F if the room temperature is maintained at 75°F (24°C)? (LF,ice = 3.33 × 105 J/kg; cice = 2.09 × 103 J/kg?°C)

A. 13
B. 1.5
C. 15
D. 16
E. 33


Answer: C

Physics & Space Science

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