[Reading Science] The Science Hidden in Soccer Field 'Goal Net'

The goal net is sharply split by the shot taken by the soccer player. Science is also hidden in the goal net.
[Photo by YouTube screen capture]

[Asia Economy Reporter Kim Jong-hwa] There are countless "geumul(net)" around us. They are made by tying multiple knots with strings and have holes of various sizes. Although commonly used in daily life, they are one of the tools whose value has been underestimated.

The most common place to find them is sports stadiums. There are soccer goal nets, basketball nets, nets used in volleyball and tennis, nets installed in the infield of baseball stadiums for spectator safety, and fishing nets used at sea, all used according to their purpose and function.

Did you know that these nets have different characteristics depending on their use? You might have thought they just separate one side from the other and prevent the ball from going out, but nets are made and used with specific features depending on their purpose and the type of sport.

The soccer goal net was first made in 1891, initially installed to catch the ball or prevent spectators from hitting the goalpost. Over time, it evolved to bounce the ball back outside the goal and to support the ball dropping vertically to the ground, considering the structure of the support frame.

Nowadays, when a goal is scored, the goalkeeper does not enter the goal to pick up the ball, right? The fact that the ball automatically bounces out of the goal is due to the performance of the goal net. Also, a spinning ball does not penetrate through the net but drops straight down because the net is thicker and stronger with enhanced durability compared to nets used for other purposes.

The grade of a soccer goal net depends on its thickness. In the English Premier League, the string used in the net is 5mm thick, which is quite thick compared to the usual net thickness of 1.6mm used in regular soccer fields and the relatively durable nets of 3-5mm thickness.

The material of the net is also made of nylon and polypropylene, which can withstand the force and abrasion of the ball. Nets used in European soccer leagues are made of high-density polypropylene with strong durability and moisture resistance.

The characteristic of tennis nets is that the ball bounces off the net and drops right in front of it without flying elsewhere. Moreover, tennis nets have a higher frequency of ball contact than soccer nets and must resist fading due to UV rays and weather. The thicker the net, the stronger its durability, so nets are made with polyethylene and polyester materials resistant to UV rays, with a thickness of 2.5 to 3.5mm.

The net dividing the tennis court also has its own function.
[Photo by YouTube screenshot]

Nets used in other sports like volleyball have similar functions to prevent the ball from flying out and to make it drop in place, but the net hanging on a basketball hoop has a different function. It is the swinging function.

When the ball passes through a rim without a net, it can look like a missed shot, so a clear visual confirmation that the ball has passed through is necessary. Therefore, the more the basketball net swings when the ball passes through, the better it is considered.

Fishing nets used at sea are also changing. About 80% of old plastic nets are discarded into the sea, causing environmental problems. Nowadays, nets are made from biodegradable plastics that naturally decompose by microorganisms. They are made using starch from corn or potatoes, aliphatic polyester, etc., and decompose into water, carbon dioxide, methane, and other low molecular compounds by mold, plankton, bacteria, and so on.

If the quality of the nets in stadiums is poor, time is wasted picking up balls that bounce off in unexpected directions, and players can get injured by balls that fly out, causing loss of time and performance due to external factors. Nets also play their own role in preventing this, don't they? Although easily seen around us, nets whose value was not highly regarded are demonstrating special abilities.

This content was produced with the assistance of AI translation services.