There is two forces that act on a soccer ball that is flying through the air and they are lift and drag forces. The lift force is the upwards or sideways force that acts on the ball. The drag force acts in the opposite direction to the ball. for example if the velocity of a ball is 70mph and the spin is about 10 revolutions per second then the lift force is about 3.5N. Then with the mass of a ball being about 410g which accelerates at 8ms^-2. Then since the ball will be in the air for about one second in a 30m trajectory the ball can curve about 4m from its original position.

soccer physics
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The drag force, FD on a ball increases with the velocity squared, v, and as long as the density, p, and the cross-sectional area, A, are not changed. FD = CDrAv2/2. The CD is the drag coefficient and it also depends on the velocity.


soccer shot

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