In 1997, in a game between France and Brazil, a young Brazilian player named Roberto Carlos, set up for a 35 meter free kick.
With no direct line to the goal, Carlos decided to attempt the seemingly impossible.
His kick sent the ball flying wide of the players, but just before going out of bounds, it hooked to the left, and soared into the goal.
According to Newton's first law of motion, an object will move in the same direction and velocity, until a force is applied on it.
When Carlos kicked the ball, he gave it direction and velocity, but what force made the ball swerve, and score one of the most magnificent goals in the history of the sport?
The trick was in the spin.
Carlos placed his kick at the lower right corner of the ball, sending it high and to the right, but also rotating around its axis.
The ball started its flight in an apparently direct route, with air flowing on both sides and slowing it down.
On one side, the air moved in the opposite direction to the ball's spin, causing increased pressure, while on the other side, the air moved in the same direction as the spin, creating an area of lower pressure.
That difference made the ball curve towards the lower pressure zone.
