Hot Air Balloon

We made a big hot air balloon. We already completed making the balloon along with the 5^th graders. Today for the Saturday’s class we decided to make it fly.

We got some old cloth and some kerosene to get hot air from the fire. We lighted it up and held the balloon on top to get hot air going in. The balloon was a big spherical structure. We waited for a long time and couldn’t get the balloon filled with hot air.

Then we discussed with the children on why the balloon did not go up. Their assumptions were

1. The Balloon had holes in the structure.
2. Hot air did not go inside.
3. The balloon was too heavy. (We weighed the weight of the balloon and it was 206 g)
4. The balloon was not properly made.

Then we decided to make a small balloon and check if it was flying. This time we made a cuboid balloon structure whose height was around 50 cm high. Again with a lot of excitement we filled the balloon with hot air. We waited and waited but it could not go up. We still don’t know the reason why the balloon did not rise up???

We are waiting to see one go up.