Physics of Bowling

The Physics of Bowling

The game of bowling can date back to as far as 3200 B.C. It wasn't until the 1930's the British brought the game to the modern day. Throughout its history physics has always taken part in every aspect of the game. It started as a very simple game with very simple objects and became a very simple yet difficult game with very difficult objects. One of those objects is the simple bowling ball.

There are four different finishes or cover stocks a bowling ball can have; they vary from plastic, urethane, reactive and particle. Each cover stock makes the ball react in different ways. Plastic balls were introduced in the 1950s. The finish is just a simple polyester type material that has a very abrasive resistant surface. Usually with bowling balls, it is possible to either sand or polish the ball to either add or take away its hook potential. With a plastic cover stock, polishing or sanding will have no impact on the ball. The friction used to hook a plastic ball relies heavily on its shell hardness, rather than its core and is best utilized on lanes with limited to no oil (dry) or for straight on spare shots. Oil on the lanes produces a small coefficient of kinetic friction. In the 1980's urethane balls were introduced to the game in replacement of the once popular rubber cover stock. They were designed to give more "hook" on the ball than plastic balls. A hook ball is when the ball goes about two-thirds of the way down the lane before curving into the pins. It can take a long time and a lot of torque on the ball to cause it to curve into the pins. Torque is what keeps the ball spinning down the lane. Urethane has higher friction in oil and on the back end of the lane compared to plastic. Compared to reactive urethane, urethane balls have less friction, especially down lane, and therefore have much tamer and mild back end reactions (think of this as a hockey stick type curve down the lane compared to a banana type curve down the lane). The tamer reaction gives up the entry angle that a reactive urethane ball provides. With less entry angle, there is less pin action and quite possibly less carry (the way pins are knocked out that aren't hit directly by the ball). Reactive resin balls absorb oil the best and more likely to develop more of a track. Reactive resin balls generally have the "banana" shaped curve to them. A track is a series of scratches along the angle the ball is consistently rolled upon, caused by a mixture of oil deposits and normal wear and tear from rolling a ball on a hard wood or plastic surface. Since it absorbs oil, it is unlikely that oil residue will be left on the ball leaving the ball with a drier surface allowing the ball to grip the lane better increasing friction and increased hook. The oil on the lane is a reactive ball's best friend as it acts as an artificial lubricant giving the ball more potential energy. A particle ball is a mixture of both reactive resin and the urethane cover stocks. Particle balls, which were introduced to the game in the late 1990's and early 2000's, tend to take off much quicker than any of the four previously mentioned balls, but reacts just like a normal urethane ball.

From the moment a bowler is about to release the ball onto the lane, gravitational potential energy takes place. It starts with the height the bowler gets on the ball before releasing the ball. The higher a bowler brings the ball in the back swing, the greater the potential energy which will eventually transfer into kinetic energy as the ball makes its way down the