Gas Law
Hot air balloons might seem magical to some people because of its ability to float in the sky, but the process that allows them to take flight is actually very uncomplicated. The balloons are prime examples of the implementation of gas laws. The physics are based on the simple principle that warm air rises in cooler air. Hot air has less mass per unit of volume.
The relevant gas law in use is Charless Law, which is V1/T1=V2/T2. The law states that raising the temperature (T1) will also increase the volume (V2), in order to keep the equation true. Generally, air is heated through the use of propane burners. When ignited, the volume of the gas increases but the balloon cannot expand much, so air will escape out of the bottom of the balloon. …show more content…
Eventually, enough air will escape that the balloon will become lighten enough to take flight. Lowering air density in a balloon without losing air pressure can be accomplished with heat. After all, pressure must remain constant in the equation V1/T1=V2/T2.
Hot air balloons have to be extremely large in order for it to work.
A cubic foot of air is calculated to weigh 28 grams. If you heat a cubic foot of air by 100 degrees Fahrenheit, it will weigh 21 grams. This means that each cubic foot in a hot air balloon can lift 7 grams. Therefore, lifting a 100-pound girl will require 1,000 cubic feet of hot air.
Descent can be achieved with two possible methods. One can simply let the air cool down, or one can open a small hole to allow more air in. The latter is the more popular and preferred method because it is a lot quicker than waiting for the air to cool. These methods make sense because it allows people to understand that without hot air, flight becomes impossible.
As for our balloon design, we will create a hot air balloon out of tissue paper. The instructions are simple; first, we will cut out our balloon shape out of a five-foot piece of butcher paper. Then, we will glue together sheets of tissue paper to create huge sheets of tissue paper. We will be careful not to use too much glue because less glue means less weight, which leads to higher flight. After the sheets are ready, we will cut out two identical balloon patterns, using the butcher paper design as a guide. Then we will glue the two pieces of tissue paper together. After that, we will tie the top section with string to hang it from a hook on a wall. This will allow us to easily work on the bottom. Bailing wire will be used to keep the bottom rings shape
constant.
Real hot air balloons have wicker baskets so that passengers can take flight. Our model balloon will not have the luxury of a wicker basket.
In conclusion, hot air balloons are ingenious due to their clever implementations of the gas laws, primarily Charless Law. They are simple but effective, which will forever earn them a place in the world of chemistry.
BibliographyHow Hot Air Balloons Work. How Stuff Works. 3 Feb 2006. Ask An Astrophysicist. NASA Goddard Space Flight Center. 3 Feb 2006. Tissue Paper Hot Air Balloon. Solo Spirit Education.
The relevant gas law in use is Charless Law, which is V1/T1=V2/T2. The law states that raising the temperature (T1) will also increase the volume (V2), in order to keep the equation true. Generally, air is heated through the use of propane burners. When ignited, the volume of the gas increases but the balloon cannot expand much, so air will escape out of the bottom of the balloon. …show more content…
Eventually, enough air will escape that the balloon will become lighten enough to take flight. Lowering air density in a balloon without losing air pressure can be accomplished with heat. After all, pressure must remain constant in the equation V1/T1=V2/T2.
Hot air balloons have to be extremely large in order for it to work.
A cubic foot of air is calculated to weigh 28 grams. If you heat a cubic foot of air by 100 degrees Fahrenheit, it will weigh 21 grams. This means that each cubic foot in a hot air balloon can lift 7 grams. Therefore, lifting a 100-pound girl will require 1,000 cubic feet of hot air.
Descent can be achieved with two possible methods. One can simply let the air cool down, or one can open a small hole to allow more air in. The latter is the more popular and preferred method because it is a lot quicker than waiting for the air to cool. These methods make sense because it allows people to understand that without hot air, flight becomes impossible.
As for our balloon design, we will create a hot air balloon out of tissue paper. The instructions are simple; first, we will cut out our balloon shape out of a five-foot piece of butcher paper. Then, we will glue together sheets of tissue paper to create huge sheets of tissue paper. We will be careful not to use too much glue because less glue means less weight, which leads to higher flight. After the sheets are ready, we will cut out two identical balloon patterns, using the butcher paper design as a guide. Then we will glue the two pieces of tissue paper together. After that, we will tie the top section with string to hang it from a hook on a wall. This will allow us to easily work on the bottom. Bailing wire will be used to keep the bottom rings shape
constant.
Real hot air balloons have wicker baskets so that passengers can take flight. Our model balloon will not have the luxury of a wicker basket.
In conclusion, hot air balloons are ingenious due to their clever implementations of the gas laws, primarily Charless Law. They are simple but effective, which will forever earn them a place in the world of chemistry.
BibliographyHow Hot Air Balloons Work. How Stuff Works. 3 Feb 2006. Ask An Astrophysicist. NASA Goddard Space Flight Center. 3 Feb 2006. Tissue Paper Hot Air Balloon. Solo Spirit Education.