How Can Soccer Players Bend Their Shots in Midair?

With the talent on tap, World Cup 2026 is sure to serve up plenty of jaw-dropping kicks, like a ball that curves in midair to go around a defender, or a shot on goal that swerves away from where the keeper thought it was headed. How is this possible? What wizardry enables a striker to change the ball’s trajectory after it leaves their foot?

It’s not magic, it’s fluid dynamics, the behavior of objects in a fluid—and air is considered a fluid, since it flows. (Kids, want to be a real-life FIFA hero? Take physics.) To really understand what’s going on, let’s model the motion of a ball, starting with the simplest and silliest scenario, then adding back elements of reality one at a time.

Soccer in Space

Why would you play soccer in space? Well, if you’ve seen the ticket prices for this year’s tournament, you might think it’s cheaper to go off planet. Anyway, say we’re way out yonder where there’s no air or gravity. The ball is at rest, and then a player in a space suit gives it a kick.

While the foot is in contact with the ball, it exerts a pushing force. The ball compresses and then rebounds, launching off the foot; all of this takes about a hundredth of a second, and a pro can easily fire the ball at 80 miles per hour.

So the applied force changes the velocity of the ball, but the thing to know is that once the ball loses contact with the foot, there is no longer any force acting on it. Which means the ball will keep moving in a straight line at a constant speed … er, till the end of time. You might recognize this as Newton’s first law.

Of course, you’d lose a lot of balls this way in space, so maybe it isn’t very practical. Let’s move the action back to Earth, but to keep it simple we’ll first assume there’s no atmosphere. Back into your space suits!

Soccer on an Airless Earth

Now there’s a new interaction involved—the planet’s gravitational pull. We can calculate this downward force as F g = m × g, where m is the mass of the ball and g is the gravitational field on Earth (9.8 newtons per kilogram). By the way, F g is what normies call an object’s “weight.”

What’s different about this force is that it's still there after the ball is kicked. The ball is moving with some velocity, and the gravitational force continuously alters its motion. The rate of change in velocity is called acceleration (a).