The refrigerator and the microwave oven were both invented by different individuals at different times:
Refrigerator: The modern mechanical refrigerator was invented by Carl von Linde, a German engineer and inventor, in 1876. He developed the first reliable and practical compressed-ammonia refrigeration system, which laid the foundation for modern refrigeration technology. Subsequent advancements and improvements were made by others, leading to the refrigerators we use today.
Microwave Oven: The microwave oven was invented by Dr. Percy Spencer, an American engineer and physicist, while he was working for the Raytheon Corporation in 1945. Dr. Spencer noticed that a candy bar in his pocket had melted while he was working on magnetrons, the microwave-emitting vacuum tubes used in radar systems during World War II. This observation led him to experiment with microwave radiation and food, ultimately leading to the development of the first microwave oven.
It's important to note that while Carl von Linde and Percy Spencer are credited with these inventions, they were the result of collective efforts and contributions from numerous scientists, engineers, and inventors over time.