Granny Throws

I remember when we would play basketball in elementary school and it was always funny to see kids throw underhand (and unfortunately, those kids were usually made fun of for it). I remember the teacher saying, "If can't throw the real way, then throw underhand," as if throwing underhand was not a "real" way to throw. However, he was mistaken, because retired NBA star Rick Barry threw underhand and had the fourth best free throw record in NBA history with a 90% success rate. A recent study from April 2017 has an explanation why this is so. According to a study by Madhusudhan Venkadesan of Yale University, an underarm throw produces a better parabolic trajectory than an overhead throw. Interestingly, as an underhand projectile has a lower speed so when it hits the rim the collision does not ricochet the ball as far back and thus it is more likely to go into the net than bouncing away. It all has to do with momentum, energy, forces and kinematics! Of course, as emphasized in class this is not a perfectly inelastic or elastic collision so it would be difficult to do the math for the collision but none the less we can begin to understand it in these terms. 

Interestingly, the authors comment that throwing underhand as an amateur is not advisable because you have greater chance of missing the target. So maybe our elementary school gym teachers should have read a physics journal and not advise this technique. 

In the end however: “So what if some call it the ‘granny throw’? What matters is that the ball goes through the hoop!” (Venkadesan). 

The scientific article can be found here:

 http://rsos.royalsocietypublishing.org/content/4/4/170136

and the commentary:
 http://www.iflscience.com/physics/throwing-granny-style-is-best-for-professional-basketball-players/

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