in a bulb there is a tungstun filament, when we switch on the bulb why it doesn't glow? give reasons
this is for DAV CBSE
class 6
Answers
Answer:
The Correct Answer is mentioned below
Explanation:
As we all know, anytime current flows through a conductor, some heat is lost, which is expressed by (I2*R).
The filament within an incandescent lamp is typically comprised of tungsten. A glass or quartz bulb filled with inert gas or evacuated protects the hot filament from oxidation. Electric current is provided to the light bulb via feed-through connections or wires embedded in the glass. The majority of bulbs are utilised in sockets, which provide mechanical support as well as electrical connections.
As a result, when a current is passed through the narrow filament, it heats up to high temperatures, producing light.
It takes some time for the filament of the bulb to heat up, which is why it takes a little time to glow, however this time is quite short.