Want to bend it like Beckham? Students at the University of Leicester in England have come up with an equation that describes in simple terms just what it takes to kick a curving shot like soccer legend David Beckham.
Well, maybe not quite so simple.
The four physics students found that the distance a ball bends (D) as a result of the Magnus effect (the phenomenon in which a spinning ball traces a curving arc as it travels through the air) is related to the radius of the ball (R), the density of the air (ρ), the ball's angular velocity (ω), its velocity through the air (v), its mass (m) and the distance travelled by the ball in the direction it was kicked (x).
Got that? Oh well. But if the equation's meaning is a bit hard to grasp, its origins sound simple enough.
"Whilst researching new ideas for a paper I read about how physics influences various aspects of football, from the clothing they wear to the effects of playing at high altitude," one of the students, 22-year-old Jasmine Sandhu, said in a written statement released by the university. "The article discussed how a new design of ball, used in the 2010 World Cup, has three dimensional molding of the panels in order to produce a more rounded ball, thus affecting the spin that can be imparted. This prompted us to examine how footballers use spin on the ball, and the factors which influence how much the path of the ball would bend."
Sandhu's co-authors on the paper describing the formula were Amy Edgington, Matthew Grant and Naomi Rowe-Gurney. Their paper was published in the University of Leicester's Journal of Physics Special Topics.
Props to the students, but if you really want to kick a curving shot like the "footballer" whose abilities inspired the 2002 movie "Bend It Like Beckham," you might be better off reading NASA's take on "bending" a soccer ball--or maybe just watching this guy.