Check todays hot topics and new pictures Today is: 28 July, 2014
Secret behind Cristiano Ronaldo’s famous `knuckleball` shot revealed

Cristiano-Ronaldo-knuckleball.jp

London, November 17 : A team of researchers has shed light on why soccer star Christiano Ronaldo’s “knuckleball” shot is so unpredictable and difficult to stop.
A “knuckleball” in soccer refers to a ball kicked at very low spin, which results in a zigzag trajectory. Along its straight path, the ball deviates laterally by roughly the diameter of a ball (0.2 m). The deviation direction appears to be unpredictable, which is extremely frustrating for goalkeepers attempting to block it.
Variations of the knuckleball are also used in baseball and volleyball, so many players and coaches want to understand the physics at play during its zigzag trajectory.
“We decided to study the knuckleball because the physics of sports is such a new field and there are many discoveries to be made,” explained Caroline Cohen, a Ph. D. student at Ecole Polytechnique’s Hydrodynamics Laboratory (LadHyX) in France.
After trying other experiments, Cohen and colleague Baptiste Darbois Texier, also a Ph. D. student, working with Christophe Clanet, a research director at France’s Centre National de la Recherche Scientifique (CNRS), focused on an approach that involves dropping steel beads into a tank of water and studying their trajectory.
They discovered that the knuckleball phenomenon occurs, but at much shorter distances. This makes it easier to observe with an ultrafast camera, which lets you see things you can’t with the “naked” eye.
“The big surprise is that every bead makes a zigzag – from a little plastic bead to a steel weight of 7 kg (15.4 lbs). We wouldn’t have bet on this occurring before we tried it, so it was quite exciting to actually see it by doing a simple experiment),” said Cohen.
The team demonstrated that – contrary to popular belief – the “knuckle effect” isn’t a result of deformations at the site of foot impact or ball seams. What’s really going on is that the aerodynamic lift forces that act on a smooth sphere can fluctuate and cause the zigzagging.
The team will reveal their findings at the American Physical Society’s (APS) Division of Fluid Dynamics (DFD) meeting, November 18 – 20, 2012, in San Diego, Calif. (ANI)

Barbados waiter gets suspended for taking selfie with Robin van Persie

London, July 27 - A waiter in Barbados was suspended from his job recently after he took a selfie with Robin Van Persie, who had come to his restaurant.  Read more »

Gazza goes on nasty Twitter rant at kids, calls teenage girls 'sad cows'

Paul-GascoigneLondon, July 27 : Former England international Paul Gascoigne, popularly known as 'Gazza', has been raving at kids and young women on Twitter and has sent nasty messages to a number of accounts, calling teenage girls 'sad cows'.  Read more »

Ishant to undergo more tests on sore leg: Joe Dawes

Joe DawesSouthampton: India`s bowling coach Joe Dawes was apprehensive about Ishant Sharma`s fitness, saying the pace spearhead will undergo tests in the next few days after missing out on the second test due to a sore leg.  Read more »

Ben Stokes, Matt Prior, testify against Ravindra Jadeja

Ben Stokes Matt PriorLondon: In a fresh twist to the alleged altercation between Ravindra Jadeja and James Anderson, two England players have testified that the Indian all-rounder had turned towards the English bowler with a raised bat during the showdown.  Read more »

Hamilton denies employing 'mind games' against Rosberg in race for F1 title

Lewis-HamiltonLondon, July 18 : Mercedes driver Lewis Hamilton has said that he is not trying to employ mind games against his teammate Nico Rosberg as both battle for the Formula One championship.  Read more »

Red Bull F1 reserve Felix da Costa to race in Formula E

Antonio-Felix-da-CostaLeicestershire, UK: Amlin Aguri have announced that Red Bull Racing Formula 1 reserve driver, Antonio Felix da Costa, will join the team for the inaugural all-electric FIA Formula E Championship beginning in September.  Read more »