How the lighting conductor protect tall buildings from damage due to lightning flash
People generally love thunderstorm. But when it produces the lightning, people get frightened since it can damage their house or kill them if it hits the ground. When the lightning strikes anything on the ground like a building, a tree or a tower, instead going straight down, it spreads along the ground first. So you don’t stand near something that is hit by the lightning, because it can hit the same place again.
In order to protect house or tall building from damage due to the lightning, Benjamin Franklin first discovered a device called the lightning conductor in 1749. It is just a copper strip which is fixed to the outside wall of the building and its lower end put deep in the ground. The other end of the copper strip projects above the highest point of the building with many sharp spikes.
When a thunderstorm began, the clouds become heavily charged. Huge electric sparks, called lightning, often happens between two charged clouds or between a cloud and the earth. If it occurs between a cloud and the earth, it becomes a great concern to man. It generally happens between two heavily charged clouds and activates opposite charge on the highest structure on the ground. As a result, trees, towers and tall buildings may be stroked by the lightning.
The protective action of a lightning conductor is based on the discharging action of points. When a heavily charged cloud move over the lightning conductor, opposite charge is activated on the spikes of the lightning conductor and the same charge passes on to the ground. Due to the discharging action of the spikes, an electric wind is established which rises up towards the cloud and partly deactivates the charge on the cloud. Therefore, the possibility of lightning strike gets decreased significantly. Sometimes even after this process, the clouds may still have some charge, so that the lightning flash may pass and hit the ground. As the spikes of the lightning conductor are nearest to the cloud, the flash hits the spikes. Being grounded, the spikes provide the electricity low resistance path, so that it can easily run to the earth. In this way, the discharge flow to the ground via the thick copper conductor and the building or tall structure therefore remains safe.