Hot Air Balloons
http://science.howstuffworks.com/transport/43-how-hot-air-balloons-work-video.htm
VIDEO
Name ______ Gr.__ Mar. __
How Does a Hot Air Balloon Fly?
-Balloons are bags filled with a light gas or hot air both so light that the balloon floats in the air.-Hot-air balloons have a burner that continually fills the balloon with warm air to keep it afloat.-Balloons are normally launched at dusk or dawn when the air is quite calm. -As the air in the bag cools the balloon gradually sinks. To maintain height, the balloonist lights the burner to add warm air again.-To descend quickly the balloonist pulls a cord to let air out through a vent at the top of the balloon.
Basket
Most hot air balloons use a wicker basket
for the passenger compartment. Wicker
works very well because it is sturdy, flexible
and relatively lightweight. The flexibility
helps with balloon landings.
Hot Air Balloon Tim
eline