A light bulb is a simple apparatus that converts electric energy into light energy. The law of conservation of energy says that energy can neither be created nor destroyed, it simply changes form. A light bulb is able to take the electricity supplied to it and change its form into something that can be used for illumination.
A bulb is made up of a positive and a negative terminals embedded inside glass, with a tungsten filament that joins the two. When electricity is supplied to the terminals, the flow of electrons heats up the thin filament in between. The electrons continue to bang against the filament until it heats up to the point that it begins to glow. This process happens extremely quickly.
The filament is encased inside transparent glass to let the light shine through and also to protect it from overheating. The air inside the glass is actually a small amount of inert gas that helps prevent the filament from becoming too hot and breaking. When the light bulb has fused it means that the thin coil inside has snapped and therefore electricity cannot flow completely through the circuit.
Can you research what is Tungsten and what makes it a good material to be used in light bulbs?
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