08 July, 2011
The Physics of Shooting a Basketball
In the event Sir Isaac Newton had not formulated the basic laws of physics while observing an apple or other objects in motion, he may very well have arrived at similar conclusions watching a basketball game. Since anything that goes up must come down, most shots require some degree of arc in order to drop into the net. However, the physics of shooting a basketball apply before a shot is ever lofted toward the basket.
Basketball players learn to generate inertia when setting up for a shot off the dribble. Moving to the right or left and planting a foot to make a jump shot is a prime example of a player utilizing the physical forces at his or her disposal. As the player moves to one side and plants a foot, the body coils. Springing off the floor to shoot a jumper not only serves to elevate the ball over a defender’s outstretched hands, the upward motion of the shooter’s body transfers a certain amount of force to the shooting hand as well.
Whether a player is shooting a jumper, hook shot or scooping an underhand lay-up, the shooting hand generates the initial physical forces on a basketball. With the exception of a slam-dunk, all shots initiate at an upward angle. The amount of force a shooter applies is directly proportionate to the height of the arc and the distance the ball travels. Experienced shooters have a way of putting more on a shot, or taking something off a shot by flexing or relaxing their wrist at the moment the ball is released.
In basketball circles, the trajectory of a basketball from the shooter’s hand to the basket is referred to as arch. Those who watch basketball frequently may have heard an announcer comment on a high-archer or a flat shot. Basic laws of physics dictate that a basketball is in the air longer during a high-arch shot from ten feet away than during a flat shot from that same distance. Shooters might use a high-arched shot to allow their teammates to get in position for a rebound. Conversely, a flatter shot might catch defenders out of position for a rebound.
A basketball has a certain amount of spin as it travels toward the basket. Unlike the seams on a baseball or the dimples on a golf ball, basketballs have a smooth texture and travel through the air at a comparatively slow speed. For this reason, shooters can loft a shot directly at the basket or a point on the backboard without the ball changing direction in flight. A jump shot has backspin that causes it to bounce off the backboard at a downward angle. Shooters put right or left spin when shooting from an angle, causing the ball to glance off the board into the basket. This technique is associated with Newton’s third law of motion regarding action and equal and opposite reactions.
- XiXinXing/XiXinXing/Getty Images