Odpowiedź:
Żarówka:
At the end of the first half of the nineteenth century were taken in various countries try to construct the electric light bulb, the device that filament (the filament) heats up under the influence of an electric current passing by him and lit. Pioneers bulbs have great difficulties to overcome: they had to choose the right material for the filament to electro-conductive without melting while under the influence of heat, and then, to get a relatively high vacuum to put in the fiber is not oxidized. Due to the above restrictions, their achievements are rather slight.
Wyjaśnienie:
Liczę na naj :)
