08 July, 2011
How Does Gravity Affect Basketball?
Every interaction you have with a basketball is affected by gravity. Gravity is the fundamental force of attraction between objects, according to The Free Dictionary. Therefore, whether you are passing, dribbling, shooting or dunking, the gravitational force of the Earth is attracting the basketball down to the court floor. By understanding how gravity affects basketball, you may be able to improve your skills on the court.
When you shoot a basketball, you exert an upward and forward force in the direction of the net. Gravity exerts a force downward on the ball, causing it to travel in an arc as it approaches the rim. If you snap your wrist at the moment you release the ball, the ball will spin from bottom to top as it moves through the air. This spin creates a difference in pressure above and below the ball, and generates an upward force. This force counteracts the downward force exerted by gravity, adding lift to your shot, increasing your range and improving the angle of entry of the ball into the net, according to Rutgers University Vision Research and Sports Science Laboratory.
Each time you dribble a basketball you exert a downward force on the ball with your hand. The ball then elastically collides with the ground and bounces back up, thanks to an upward normal force exerted by the ground on the ball. The more elastic the collision between the ball and the ground, the higher the ball bounces. You may have noticed that if you dribble a deflated ball, you must exert significantly more force with your hand than if the ball were well-inflated. This is because the higher the air pressure of the ball, the more elastic the collision between the ball and the ground. For this reason it is important to use a well-inflated ball when playing basketball.
When you pass a basketball you exert a forward force toward a target player, much like when shooting. The ball travels in an arc rather than a straight line. If you do not account for gravity, the destination of your pass will be lower to the ground than anticipated, which will make your pass difficult for the target player to handle. For this reason, you must exert a slight upward force and pass the ball slightly higher than the target to compensate for the downward force of gravity.
The downward force of gravity on a basketball is dependent on its mass -- the heavier the ball, the greater the force of gravity exerted on it. A regulation basketball is 1.3 lbs., according to Jump USA. When playing recreationally, however, you may encounter a basketball that is heavier or lighter than regulation mass. You must therefore adjust the amount of force exerted when passing and shooting. For example, if playing with a heavier ball, you must exert a greater upward force when shooting to compensate for the increased downward force of gravity.
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