IPad Apps

rocks and minerals app
Rocks and Minerals
structure of earth app
Structure of earth
simple machines app
Simple Machines
magnets app
adaptations in animals app
Animal Adaptations
adaptations in plants app
Plant Adaptations
diseases app
solar system app
Solar System

Welcome to FunAppSchool


IPad and IPhone Apps

Educational Games for IPad and IPhone. English Grammar and Science Apps for Elementary and Middle School Kids.

Electric Light Bulb

The history of the electric light bulb began in 1809 when English chemist Humphrey Davy invented it.

Davy’s light bulb worked by being connected to a battery by two wires, with the other ends of wires being attached to a strip of charcoal.

When the charcoal (form of carbon) gets charged by the atmosphere electricity is produced which fires the light bulb. This was the first arc lamp.

In 1820, Warren De La Rue placed a coil made of platinum into an empty tube and allowed an electric current to pass through to form the first known proto-light bulb.

In 1875, Henry Woodward and Mathew Evans licensed the first light bulb, and three years later, Sir Joseph Wilson Swan was the first person to invent a practical light bulb.

Sir Swan’s light bulb burned about 13.5 hours and was therefore considered very usable.

You see, the workability of the light bulb depended on the filament that was used. A filament in this case is very thin wires, which light up with the current.

Over the years inventors experimented mostly with this filament, trying to find the perfect filament material that would keep the bulb burning longest.

Sir Swan’s light bulb burned longer than all others invented before it because it was made of carbon fibre, which is derived from cotton.

Thomas Alva Edison (who many mistakenly assume invented the light bulb) invented a carbon filament, which he placed in a bulb without oxygen.

This new creation burned for 40 hours, almost three times the amount of Sir Swan’s but kept working on it and used a bamboo-based filament which burned for 1200 hours!

However, one of the main problems with all these filaments were that the longer they burned within the bulb, the light bulb turned dark.

Between 1906 and 1910, tungsten filaments were introduced into Edison’s incandescent light bulb and they outlasted every one before them. Soon it was open for public to buy.

In 1925, the first frosted light bulbs were produced, and in 1991, the Philips Company produced a magnetic induction light bulb that lasted for 60,000 hours!

So how does this amazing light bulb work? When the light bulb is fixed into the electric socket, the electrical circuit (part of which is in the filament of the bulb) is complete.

This is what allows the electricity to flow through the live wire, in through the socket, and through the filament.

The magic of the tungsten filament is that it does not let electricity flow very easily. This is called electrical resistance. Therefore, when the power circuit is complete electricity must push itself through the tungsten filament.

The tension it creates when pushing heats up the tungsten so much that it begins to glow. This glow is what gives us light.

Therefore, you may wonder why some bulbs are brighter than others are. This depends on the amount of electrical resistance the tungsten provides.

The box (and the top of the bulb) usually has a number printed on it, which is expressed in Watts (the measure of electrical energy, named after Thomas Watt).

The higher the amount of watts, the more electricity the bulb will need, which means the light, will be brighter.

Most of the new types of light bulbs use up more electricity compared to the amount of light they produce.

To solve this problem, light companies have manufactured compact fluorescent lights or CFLs.

These bulbs are considered energy saving because instead of electricity pushing through the tungsten tube, the electricity flows through a glass tube that is filled with argon and phosphor gas.

These bulbs are safer but need to be handled safely as the glass is very sharp and the chemicals inside (if they break) are very poisonous, especially mercury.

When disposing of light bulbs (which ever they are) it is important that they be done in a safe and environmentally friendly manner.