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HISTORY
1930: proposal for the use of electric field for heating dielectric material.
1945: Heating effect of microwaves was discovered accidentally.
1947: World’s first microwave oven was discovered.
1954: An improved version came into existence.
1967: The world’s first popular home model was introduced.
PERCY SPENCER- the inventor
Born in Howland, Maine, orphaned at a young age and raised by his aunt and uncle.
never graduated from school. Went to work in a mill at a age of 12.
In 1912, joined the navy to learn wireless telegraphy.
joined Raytheon company in 1920.
In 1941, magnetrons were made at a rate of 17 per day at Raytheon.
Percy Spencer devised a more efficient way to manufacture them. Magnetron production increased to 2600 per day.
For this contribution he was awarded distinguished public service award.
with the advent of some observations regarding the heating effect of magnetron in 1945, world’s first microwave oven was discovered in 1947.