INTRODUCTORY VIDEO ;
Have you ever noticed a golf ball carefully? If you have, you must be aware that it has some small spherical dots on it. You might have thought that why do golf balls, in particular, have these small dots. These dots are called “dimples”, and these dimples are not there just for the sake of design. In each manufactured golf ball, at least 300-350 dimples are embedded. These dots may seem too small to have any effect on the ball itself, but, they actually play a significant role in the trajectory of the ball. These dimples are the reason, why you are able to hit such wide-ranging shots with the golf stick.
Now let’s consider what all forces are acting on the ball in a particular moment, while it is traveling through the air. So basically, whenever a body travels through space, it is being acted upon by multiple forces; First of all, gravity is constantly pulling down the body with a particular force (mg).
The aerodynamical forces acting on the body can be broken down into two major components: drag and lift. Drag can be defined as a force that is generated by the interaction of a solid with the air, acting in the direction, opposite to the direction of the motion of the ball. In simple words, drag is a force that constantly tries to pull back the body traveling through air. The second major force is called lift. Lift always acts in a direction, perpendicular to the motion of the body. Lift generally acts in an upward direction, in order to counter the force of gravity; but it can act in any direction perpendicular to the motion of the body. According to aerodynamics, when a body is traveling through the air, the air tends to cling to the surface of the body. Then, the air moves towards the backside of the body and then eventually separates from the body, making a turbulent wake region on the backside of the body. Similarly, let’s imagine you hit a golf shot with the maximum amount of force you can apply. Now, the ball has a good enough velocity and it is traveling through air. As we understood at the beginning of the paragraph, the same phenomenon is happening with the golf ball. Now, here come the dimples, which make all the difference. Dimples on a golf ball create a thinner turbulent boundary layer of air that clings to the ball's surface, allowing the ball to have a lesser magnitude of drag force, which helps the ball to travel farther than a normal smooth ball.
We conclude that the small dimples present on the golf ball help the ball to have a more streamlined structure, which ultimately helps the ball to have a long trajectory as compared to a smooth ball.