How does a kite work?
A kite can fly because it is held by a string while the wind
pushes it up. As the string prevents the kite from being blown
away, the wind pressure builds up against the kite's sail and lifts
it up in the air.
If the kite is well balanced, it will climb up until it reaches
a stable position where all the forces involved are evened:
- the upward lift force from the wind pressure
- the downward forces of weight of the kite, of the weight of
the line, of the wind pressure on the line, and of course the
downward force of your pull on the line
It you let go the line, the kite runs away, as if it was in a
riverflow, and soon reaches the same speed as the wind. Then there
is no longer any relative wind pressure to hold it up, so it will
But if you stop the line and hold it, it will go up again!