Hot Air balloonsby:dunningh681
How they where invented
The first idea of a flying object using heat came when a scientist observed a fire in his living room fireplace he realized the embers of the fire moving up like they were being

blown the man wondered if he could test that on a larger scale but it wasn't until a couple of years when his idea was finally tested,
hot air balloon diagram.jpg
hot air balloon diagram
Two brothers created a balloon which was powered by a large fire below the heat from the fire did the same to the balloon as it did to the embers it flew up and that was the first recorded balloon flight after it was determined safe enough they put animals and then people to create an invention that would exist for centuries.

How they work

Today hot air balloons have 3 main parts, the envelope, the basket and the burner. After the burner shoots flames fills the envelope with hot air the air in it is less dense than the air around it like a wooden plank under water the wood is less dense than the water and it floats up. The balloon starts out rising slow because there is not much hot air in the balloon but in a short period of time hot air fills the envelope and the balloon rises quicker. A parachute at the top of the balloon can be pulled to open and let hot air escape and colder more dense air take its place. With heavier more dense air in it the envelope the balloon starts to descend. For a balloon to carry a heavy load the balloon has to be bigger to hold more hot air.

Conclusion
Today balloons have many shapes and sizes and there are many festivals that involve many hot air balloons if you go to one of these you can understand how they work and how they where invented so if you are riding or even piloting one of these balloons you can know how they fly. For more info on gases and density check out these cool blogs.look in the gas section of this blog for info on gasses.

220px-Balloon_fuel.jpg
burners creating hot air

Montgolfier-balloon.jpg
early hot air balloon
Glossary

Dense: the closeness of things [very compact],[not compact]

Descend: to slowly lower

Envelope: the balloon itself

Cites

David Macaulay, The New Way Things Work, Boston, Houghton Mifflin Company. 2009. Print.

. Lindsay Lowe, ED, Matter Energy and Heat, Tucson, AZ. Brown bear books. 2010. Print.

Physical Science: States of Matter Discovery Education, 2002. Full Video.

Discovery Education. Web. 27 September 2012

Wikipedia contributors. "Hot air balloon." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 26 Sep. 2012. Web. 28 Sep. 2012.