IT'S BAMBOO BURSTING SEASON: WHAT'S THE SCIENCE BEHIND THE EXPLOSION?

Have you ever come across the traditional game of bamboo bursting in Saint Lucia? Traditionally beginning November 2 and lasting until December end, echoes of explosive sounds are heard over the hills. It’ll often begin by sundown and last deep into the night.

Credits: The St Lucia Star

Participants in this traditional folk method of welcoming Christmas are primarily young boys. With next-to-harmless, non-ballistic cannons, each team tries to outdo each other in achieving the loudest ‘booms’ This game involves a bamboo tube or node filled with a mix of water and fuel, which produces an explosive sound like a cannon when ignited. It has been a popular game played by children since the 1990s, and it is still played in rural areas where bamboo is widely available.

While playing this game may seem like a fun activity, it is intriguing to wonder whether there are any physics principles at work behind this game. After all, the explosive sound and fire release sound like the result of some physical process. In this article, we will explore the working principle of bamboo cannons in terms of energy physics.

The Science Behind the Explosion

If you want to understand the working principle of a bamboo cannon, you need to start with the science of sound production. The sound produced by the bamboo cannon is an example of explosive sound, which is a sudden and brief release of energy. Explosive sound is caused by the rapid and violent expansion of gases, which creates a shock wave that travels through the air and reaches our ears.

In the case of a bamboo cannon, the water and fuel mixture inside the bamboo tube can be considered as the medium that stores energy. When heat is applied to this mixture, the fuel reacts with the water to produce gas. The pressure of the gas builds up inside the bamboo tube until it reaches a critical point where it cannot hold any more pressure. This results in a sudden and explosive release of gas, which in turn creates the shock wave we hear as the sound of the bamboo cannon

The energy released by the reaction between water and fuel is similar to the energy released in a chemical explosion. The difference is that the energy release in the bamboo cannon is not as intense or dangerous as in a chemical explosion, since the quantity of water and fuel used is much smaller. However, the principle of energy release is the same, and it is an excellent example of the conversion of chemical energy into sound energy.

The Role of Kerosene

The fuel mostly used for bamboo bursting is kerosene. Kerosene is a flammable liquid composed of hydrocarbons, which can be burned to produce heat and light. When kerosene is mixed with water inside the bamboo tube and ignited, the combustion of kerosene produces a flame and an explosive sound. Kerosene reacts with water to produce gas, which creates an explosive sound. 

Conclusion

In conclusion, the working principle of a bamboo cannon in terms of energy physics involves the conversion of chemical energy into sound energy. When the water and fuel mixture is heated and ignited inside the bamboo tube, it produces gas, which creates an explosive sound due to the rapid expansion of gases. The fuel most often used in bamboo cannons is kerosene, which react with water to produce gas and an explosive sound.

Understanding the physics principles behind the bamboo cannon can be an interesting exercise in energy physics. It demonstrates the concept of energy conversion and the production of sound through the release of energy. So, next time you hear the explosive sound of bamboo bursting, you can appreciate the science behind it.