Scientists investigate the curious phenomenon of golf balls bouncing out of the hole after seemingly sinking.
Golfers around the world know the frustration: a perfectly aimed putt rolls into the hole—only to bounce back out. This puzzling behavior has now caught the attention of scientists, who have taken a closer look at the physics behind it. While their findings may not eliminate the frustration, they do offer a deeper understanding of the forces at play.
Golf has become a global sport with millions of fans and players. Its popularity spans from major international tournaments to the betting industry, where golf has carved out a significant niche. The sport even serves as a gateway into the world of casino games, with platforms offering everything from high-RTP slot machines to roulette and blackjack. But no matter the setting, golfers everywhere have experienced that maddening moment when the ball seems to have a mind of its own.
Why Golf Balls Bounce Out of the Hole
The moment is familiar: the ball rolls straight toward the hole, appears to drop in, but then inexplicably pops back out. According to a study by scientists from the UK and Hungary, two main factors are responsible—tilt and spin. The ball’s angle and its rotational movement play a crucial role, especially the spin around its own axis.
Two Types of Lip-Outs
Researchers Stephen Hogan from the University of Bristol and Máté Antali from Széchenyi István University in Györ published their findings in the Royal Society Open Science journal. They identified two types of lip-outs: edge lip-outs and hole lip-outs. In the first case, the ball’s center of mass doesn’t align with the hole’s center, and the tilt isn’t steep enough to counteract the rolling motion. As a result, the ball veers off and rolls away.
Spin Is the Real Culprit
In the second scenario, the ball seems to vanish into the hole but then reemerges. This is due to spin acting in a different direction than the ball’s roll. The spin causes the ball to rotate back out—unless it touches the bottom of the hole, which would disrupt the spin and keep it in place. This phenomenon only occurs if the ball hasn’t yet hit the hole’s base.
There’s still one more mystery to solve: sometimes the ball hits one edge, rolls along the opposite rim, and either falls in or returns to the green. The researchers acknowledge that this variant remains unexplored. Still, their work offers a solid scientific foundation for understanding one of golf’s most annoying quirks. Whether it will ease players’ frustration remains to be seen.