Science Questions

I went on a hot air balloon, and they guy who was flying said that if you lit a candle the wind wouldn't make the flame flicker because the balloon is flying with the wind. David from Melbourne

This would be the case if the wind was completely uniform and moving at a constant speed, because the balloon will get blown at the same speed as the wind so you wouldn't feel it.  However if the wind changes speed in a small gust it will take a while for the balloon to catch up with the air and you would feel a gust, or if the wind isn't uniform over the whole balloon you will not be travelling at the same speed as the air near the basket so you will feel some wind.  Also a balloon works because hot air is less dense than cold so rises, this means that air around the balloon will get heated up and rise, so the balloon itself will create weak air currents.

July 2007