3. Two identical refrigerators are plugged in for the first time. Refrigerator A is empty (except for air) and refrigerator B is filled with jugs of water. The compressors of both
refrigerators immediately turn on and begin cooling the interiors of the refrigerators.
After 2 hours, the compressor of refrigerator A turns off while the compressor or
refrigerator B continues to run. The next day, the compressor of refrigerator A can be
heard turning on and off every few minutes, while the compressor of refrigerator B
turns on and off every hour or so (and stays on longer each time). Explain these
observations.