Final answer:
Golf balls need dimples to reduce aerodynamic drag and enable them to travel further. Dimples create turbulence that allows the ball to fly more efficiently. While many golf balls conform to standards making them similar, companies innovate to differentiate and improve performance.
Step-by-step explanation:
You asked, why do golf balls need dimples on them? The primary reason is to reduce aerodynamic drag and enhance flight performance. Over 1800 golf balls from more than 100 companies meet the USGA standards, showing that while they must adhere to certain regulations, they can vary in features such as dimple patterns.
Dimples on a golf ball create turbulence in the air surrounding the ball which, counterintuitively, reduces the drag force acting on the ball as it flies through the air. This turbulence makes air stick to the ball a bit longer and reduces the wake behind the ball. Reduced drag results in golf balls traveling further than they would if the balls were smooth.
While professional players like Tiger Woods may distinguish between different golf ball brands and models, most are monopolistically competitive. The average amateur golfer may not notice significant differences for casual play. However, the golf industry, which sees retail sales of about $500 million per year, continuously seeks to innovate and improve golf ball technology, including dimple design, to enhance performance and attract consumers.