Search results
Results from the WOW.Com Content Network
A microwave oven or simply microwave is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. [1] This induces polar molecules in the food to rotate and produce thermal energy (heat) in a process known as dielectric heating.
The magnetron emitted microwaves into the metal box blocking any escape and allowing for controlled and safe experimentation. He then placed various food items in the box, while observing the effects and monitoring temperatures. There are no credible primary sources that verify this story. [citation needed]
He investigated cooking with microwaves and invented the microwave oven, consisting of a magnetron feeding microwaves into a closed metal cavity containing food, which was patented by Raytheon on 8 October 1945. Due to their expense microwave ovens were initially used in institutional kitchens, but by 1986 roughly 25% of households in the U.S ...
How the Microwave Was Invented by Accident Pictorial Parade - Getty Images Yes, the microwave oven was invented accidentally, when a test for a magnetron melted an engineer’s snack in 1946.
The Hungarian engineer Dénes Mihály patented an image scanning with line deflection, in which each point of an image is scanned ten times per second by a selenium cell. August Karolus (1893–1972) invents the Kerr cell , an almost inertia-free conversion of electrical pulses into light signals.
In 1402, Yi Hoe and Kwan Yun created a world map largely based from Chinese cartographers called the Gangnido map. It is currently one of the oldest surviving world maps from East Asia. [66] Another notable pre-modern map is the Cheonhado map developed in Korea in the 17th century. [67]
The De Virga world map was made by Albertinus de Virga between 1411 and 1415. Albertin de Virga, a Venetian, is also known for a 1409 map of the Mediterranean, also made in Venice. The world map is circular, drawn on a piece of parchment 69.6 cm × 44 cm (27.4 in × 17.3 in). It consists of the map itself, about 44 cm (17 in) in diameter, and ...
Early world maps cover depictions of the world from the Iron Age to the Age of Discovery and the emergence of modern geography during the early modern period.Old maps provide information about places that were known in past times, as well as the philosophical and cultural basis of the map, which were often much different from modern cartography.