Discus flying farther when cross wind blows

The discus throw is one of ancient Olympic pentathlon (long jump, discus, javelin running and wrestling). Image of discus throwers figured in advertising for early modern Games and used for the main posters in 1920 and 1948 summer Olympics. The discus which has wood, plastic or fiberglass rim is a heavy lenticular disc with a weight of 2 kilograms and diameter of 22cm for the men’s event and a weight of 1kg and diameter of 18.1cm for the women’s event.

In order to throw farther, the competitor should spin their body rapidly by using centrifugal force. Unlike the shot put, the disc gets more air resistance due to wide surface. Therefore, the inclination of a disc itself (elevation) must be considered and strong rotation must be given to the disc.

The interesting fact in the discus throw is disc will go farther when cross wind blows. The reason why this strange phenomenon occurred is the lift force in the bottom of disc similar to the force keeps an airplane in the air. The best angle of inclination for lift force is 20 degrees.

The final match of discus in World Championships in athletics will take place on Aug 28 for women’s and Aug 30 for men’s respectively.