Physics forced to come up with whole new equation to explain “impossible” soccer kick

IO9: Physics forced to come up with whole new equation to explain "impossible" soccer kick

In 1997, Brazilian soccer player Roberto Carlos scored on a free kick
that first went right, then curved sharply to leftwards in what looked
like a physics-defying fluke. We've finally discovered the physics
equation that shows it was no fluke.

The amazing goal, which
left French goalkeeper Fabien Barthez too stunned to react, was scored
during a friendly match in the run-up to the 1998 World Cup. A group of
French scientists, perhaps desperate to prove that at least the laws of
physics aren't actively rooting against their national team, were able
to figure out the trajectory of the ball and, with it, an equation to
describe its unusual path.

It all comes down to the fact that, when a sphere spins, its
trajectory is a spiral. Usually, gravity and the relatively short
distance the ball travels covers up this spiral trajectory, but Carlos
was 115 feet away and kicked the ball hard enough to reveal its true
spiral-like path. As you can see in the diagram up top, the ball would
have kept spiraling if gravity (and the netting) hadn't gotten in the
way.

This means that anyone can perfect this spiral trajectory if they're
able to hit the ball far enough and with sufficient force, which might
explain why Carlos has pulled off this supposed once-in-a-lifetime fluke
so often.

In the first video, it looks to me like the ball barely makes more than one revolution before getting to the goal. It looks sort of like a knuckle ball.

I played fullback in college. (I call it playing. Others refer to it as my foray into comedy.) My friend Dave had a banana kick that was wicked. (You more or less
slice through the ball using the outside edge of your foot causing the
ball to slice away from that foot. You use the inside to go slice the
other way.)  It always amazed me what some of the strikers could do with a ball, particularly on set plays.