Why does the light bulb burn out?

Filament in the bulb

A filament is the part of an incandescent bulb that glows. It is a thin wire, usually made of tungsten, that shines brightly when current flows through it.

The filament is heated to more than 3,000°F (1,600°C) by the current flowing through it. The heat causes the atoms in the tungsten to vibrate vigorously and emit light as they collide with other atoms around them – a process known as glowing.

Exposed to electricity

The bulb is made of tungsten, which is a conductive metal. When you flip a switch and apply an electric current to the wire filament inside the bulb, electrons flow through it. When they do, they generate heat and make the filament glow white (heat up). At this temperature, visible light is emitted from the excited tungsten atoms (the filament glows).

Light flow

Light is a form of energy and transfers energy from the bulb in the form of heat. When the filament heats up, it produces an electric current that flows through the metal wires inside the bulb. This current produces heat and light as it passes through a gas-filled glass tube enclosed inside the bulb (Figure 2).

Live wire

So how does a light bulb actually work? Why does it burn out?

The answer is that it all depends on the filament. The filament is the part of the bulb (a long piece of metal) that glows when current flows through it. Electrons flow through this filament, heating it and thus producing light. Incandescent bulbs have filaments made of tungsten or carbon; fluorescent bulbs have filaments made of mercury vapor (if you’ve ever seen one explode, you’ll know why).

For an incandescent bulb to work properly, its filament must be heated enough for some electrons to escape the atom without being absorbed by other atoms nearby – a process called ionization. If too few electrons escape ionization and are instead absorbed by the surrounding atoms, they will get too hot and begin to damage themselves or turn into positive ions – making everything around them even hotter!

Electron cloud

Electrons are negatively charged, which means they are attracted by a positive charge. When you turn on your light bulb, electrons flow from the filament to the positive terminal and through the filament. This creates heat and pressure in the metal wire, which causes it to glow brightly. The filament is what creates most of the bulb’s visible power: its color determines its temperature; higher temperatures produce brighter colors.

Conclusions: The more electrons flow through a filament, the faster it burns.

The more electrons flow through the filament, the faster it will burn.

As the bulb heats up, the filaments get hotter and hotter until they melt. If the filament is no longer able to conduct electricity, then it burns out and stops working.

Summary

The more electrons flow through the filament, the faster it burns.