I’d like to told my stories in the making of this project, shortly named RBL (from Research Based Learning). This is a Science Project from Physics. This year’s project is to make a mini hot air balloon. We made a group to research about it. My group consist of 8 people: Rey, Ucik, Sifa, Dea, Alda, Dhani, Dian, and myself. We were given 3 weeks to make the balloon. We thought at first this task was easy, we just have to do it neat and procedural.
We started our first trial on the 2nd day. We tried plastic bags with 4 candles as the fuel. It didn’t succeed. We tried 3 kinds of plastic bags. First it was laundry bag, quite big and heavy, it’s only bulged until the plastic got blackened but didn’t float. The second was a small thin plastic bag, it burned because then top side of the plastic is too hot. The third was a transparent Low Density Polyetylene (LDP), its’ side part got caught in fire and our plastic got burned also. We stopped our first trial after that, and discussed another way.
Several days later, when our group can’t meet up together, I tried using with many plastics types. I used groceries plastics, two trials. One formed like a cylinder, one like a real air balloon. Both of them failed. Probably because the candles are too heavy. Then I tried with a bigger plastics I bought from the store, it didn’t work because it was too heavy, the big volume still can’t put up with the heavy layer of plastic.
Our group had done some research on the internet. About the principle, about it’s structure and materials, and tips to make a good hot air balloon. But we still couldn’t make it. We tried crepe papers with cylindrical shape. We had changed the fuel to oil, spiritus, and parafin. We tried oil papers, bread paper, kitchen paper and other papers. We spoke to many successful fellows. We prayed and patiently made so many balloons.
The day before the test, we still haven’t made our balloon. I was so anxious, several groups have succeeded. Fortunately the reports was almost done, it left to photos and calculation (we couldn’t do it before we succeeded making one) I asked my friends to gather in the morning, and we made more attempt, with precise calculation and shape. Our balloon (the yellow and green one in the photos was so good. It stood upright with symetrical shape. But the parafin fuel couldn’t lift it! It only floats, not fly. I was almost lost of hope. But then, in the afternoon, I got information from my friends in SITH R that there’s a market near ITB that sells sheets for making Air balloon. He had tried it and success in one trial. So we rushed to a market and found a good thin sheets. We skipped two lecturers to make the balloon. And at the dawn, we tried our 13th trial balloon with a big hope. And it Flew!!!!!!! We were suprised and jumped happily. It flew really high (we tied it to a rope so it didn’t lost). Oh, it’s really a relief, on the last minute, we finally got our balloon fly! :D. I finished the reports at night with the volume and density, using Newton’s 2nd law and Ideal gas law. Indeed, the net force is upright. 🙂
The next day, the real test started. We tried our balloon in Saraga. Almost all the groups in my class succeeded, there were 2 group failed, unfortunately. Our balloon flew really high and we were all so happy. I gave thanks to God, for what He did was a so good. Thanks for this experience God. I learned lessons from this project.