1. Until the early17th century, People used wooden balls for playing golf. Then the Featherie ball was invented. A Featherie is a hand sewn cowhide bag stuffed with goose feathers and coated with paint. The Featherie remained the standard Golf ball for more than two centuries, due to its superior fight characteristics.

2. ln 1848, Robert Adam Paterson invented the Gutta Percha ball. Gutties had textured surfaces to improve their aerodynamic qualities and where also cheaper to produce. They only replaced feathered balls completely within a few years.

3. In the 20th century, multi layer balls were developed, first as wound balls consisting of a solid or liquid-filled core wound with a layer of rubber thread and a thin outer shell. This design allowed manufacturers to fine-tune the length, spin and ?feel? characteristics of balls. Wound balls were especially valued for their soft feel.

4.These days golf balls are made of cores of titanium compounds, hybrid materials, softer shells and a more pressurized core. They usually consist of a two-three, r four layer designs, consisting of various synthetic materials like surlyn or urethane blends.

Characteristics of modern golf balls:

? The minimum of allowed diameter of golf ball is 42.67mm and its mass may not exceed 45.93g.

? Modern golf balls have a two, three, or four layer design constructed from various synthetic materials.

? The surface of the ball usually has a pattern of 300-400 dimples designed to improve the balls aerodynamics.

? Materials and the method of construction used greatly affect the ball's paying characteristics such as distant trajectory, spin and feel.

? Harder materials such as surlyn are used, which result in ball's traveling longer distances.

? Softer covers such as balata tend to generate higher spin, more ?feel? and greater stopping potential.

Golf balls are separated into 3 groups depending on their construction two, three, or four-piece covers generally four-piece golf balls tend to be the most expensive but price is no assurance of quality.

Aerodynamics:

? When we hit a golf ball, the impact which lasts less than a millisecond, determines the ball's velocity. Launch angle and spin rate, all of which influences its trajectory.

? A ball moving through air experiences two major aerodynamics forces.

1. lift

2. drag

3. Drag slows the forward motion. Whereas lift acts in a direction perpendicular to it. The magnitude of these forces depends on the behavior of the boundary layer of air moving with the ball surface.

? Dimples are designed to increase the shape and lift and drag forces by modifying the behavior of the boundary layer. It should be noted that drag and lift forces exists also on smooth balls. Dimpled balls fly farther than non dimpled balls due to the combinations of two effects.

? The backspin as we discussed before generates the lift by deforming the airflow around the ball. A back spinning ball experiences a upward lift.

? The order to keep the aerodynamics optimal, the ball needs to be clean; golfers can wash their balls manually. Mechanical ball washers available.