In 1997, in a football match between France and Brazil, the spectators were able to witness an amazing event. That was the free-throw shot by Roberto Carlos, who was a young player on the Brazilian team at that time. The distance between the football and the goal was thirty-five meters. There was no direct line between him and the goal (goal net), as there were several other players in front of him to block the football. Carlos hit the football to the right side, avoiding the players covering the goal. However, the ball, which was initially drawn out of the goal, turned back to the left side and went to the goal, leaving nothing for the opposing players to think about. Brazil was able to score a goal with this wonderful trick. Now let’s find out how the Brazilian player Carlos, who surprised everyone, created this wonderful bend in football.
The science of Carlos’ hit
According to Newton’s first law, objects in motion must move with uniform velocity in the same direction until an external force is applied. When Carlos hit the football, he gave it direction and velocity. In this way, the ball did not travel in a straight path but was able to create a bend in it because of another force acting on it. When Carlos hit the lower right corner of the football, it rose up. So the football rose up, and the football rotated around its axis. When the ball moves forward in a straight path, it cuts the air in front of it. Because of this, due to the resistance of the air, the velocity of the football is gradually reduced. Not only this, but because the football rotates around its axis and moves forward, one side of the ball moves in the direction of the air and the other side moves against the direction of the air. This increases the pressure on the side where the football spins, opposite the direction of air travel. In the same way, on the side where the football rotates in the same direction as the air travels, there is less pressure. Due to this pressure difference, a force is generated from the direction with more pressure toward the direction with less pressure. This force is called the “Magnus force.” Because of this Magnus power, the direction of football changed. This phenomenon is described as the Magnus phenomenon.