Why Shoot With An Arc?

By Don Kelbick

Is the hole in the rim the same size all the time?

Do you think that’s a strange question?

When I was in pilot training, I learned that the outer end of a propeller moves faster than the inner end. I could not figure out how that could be. They are all connected to the same hub and it only spins at one speed.

Well, when you look at the definition of speed, it is the time it takes to move a mass over a prescribed distance (e. g. miles per hour). Since the far end of a prop has to travel a longer distance than the part near the hub, but must complete its trip in the same amount of time, it must be moving faster.

So, I ask again, is the hole in the rim the same size all the time?

I would argue “No!”

Try this experiment. Get a round trash pail. Put it on the floor and look down on it. How big is the hole, how much do you see? Now, pick up the pail and put the rim of the pail at eye level. How big is the hole, how much do you see now?

Same pail, same hole, different situations. Looking at the hole with the pail on the ground you can see a big hole. Looking at it at eye level, the amount of the hole you can see is very small.

Now imagine your eyes are the ball when you are shooting a basketball. Which angle gives you the best chance to put the ball in the basket? The answer is obviously the angle in which it can see the most hole.

The ball has the best chance to go through the hole when it enters from above. We have all heard that 2 basketballs can go through the hole at the same time. But that is only true when the balls enter from directly above, when the hole is bigger. In fact, when putting balls in the hole from directly above, you can fit 5 balls in the hole at once (I said in the hole, not through).

When shooting a low trajectory shot, if the ball hits the rim, the forward momentum will overpower the downward momentum and probably skip forward off the rim. With a higher trajectory, a larger hole, more downward momentum, the ball hits the rim and rolls through the hole.

The optimum arc is different for everyone because there is a comfort level here. There is a point where too much arc also adds more distance to the shot and it could turn a 20 foot shot into a 25 foot shot and now you are out of your range, but I would say use as much arc as you can comfortably use.

So, is the hole the same size all the time?

For more information on Don Kelbick go to http://www.DonKelbickBasketball.com.


  1. DaleH — June 25, 2010 @ 12:41 pm

    I hate to nit-pick because this is a simple but often overlooked point to emphasize to young players. However I believe there are a few inaccuracies in this article.

    First, it is incorrect to state that 5 basketballs will fit in a hoop.

    Area of hoop = pi * (radius ^ 2) = pi * (9 ^ 2) = 254.47 square inches

    The radius of a men’s basketball (29.5″ circumference) = circ / pi / 2 = 4.70

    Thus, the circular area of a men’s basketball = pi * (4.70 ^ 2) = 69.40 square inches

    Therefore, the theoretical number of basketballs which can fit into a standard basketball hoop = 254.47 / 69.40 = 3.67

    Thus, the area of a hoop is 3 2/3 times the area of a standard men’s basketball. Of course, because of the actual shape of the ball, 3 basketballs can’t go through a hoop at one time.

    In fact, I don’t believe 2 baskteballs can go through the hoop at a time. The diameter of a 29.5 baskteball is 9.39 inches, which is a bit more than 3/8 of an inch greater than half the diameter of the 18 inch hoop. A women’s ball (28.5) has a diameter of just a hair over 9 inches (9.07 inches), so 2 women’s balls won’t quite fit either (unless you give a bit of a shove).

    Of course, all this is secondary to the main point of the article, which is an important point: shots with decent arc have a better chance of going in than flat shots.

  2. Joe Haefner — June 25, 2010 @ 1:39 pm

    Thanks for the calculations, Dale.

    Those calculations are also assuming that all of the basketball are in there at the widest point. Maybe the basketballs are sitting in the hoop, but not at the widest point? I’m curious. I might have to test it out myself.

    But like you said, that’s not the point of the article.

  3. Jeremy — June 26, 2010 @ 8:39 am

    This Noah shooting chart seems to confirm Dale’s calculations http://www.noahbasketball.com/pdfs/What_the_Ball_Sees.pdf

    Most of my internet googling seems to come to the same conclusion.

    That being said I’m sure we all have seen it happen where two or even three balls get caught in the net at the same time. I would say because these calcs assume at exactly the same time they don’t take into account the downward force that may cause the balls to be able to squeeze through or the fact that if one ball is a tenth of a second a head of the other ball they can both get through.

    Anyway these are all technicalities and the whole premise still rings true that the hoop is a heck of a lot bigger than most people think and the margin for error and still swishing a shot is very large if you have a good downward trajectory on your shot.

    Today so many kids shoot these line drive wrist flip shots that have no margin for error and then wonder why they can’t shoot 50% from the line (many NBA players included) – 90% of the time its the trajectory of the shot.

    Shameless plug for Tom Nordlands Swish method of shooting here – shooting really is that simple.

  4. I KNOW — July 13, 2010 @ 3:03 am

    If you get yourself above the rim on a ladder it IS possible to get 2 balls through the hoop at the same time. They only just fit, but it does work, I have tried it.

  5. Peter — July 13, 2010 @ 3:06 am

    Don’t forget also the rebounding advantage on a high arc shot. The ball will generally drop inside the paint instead of rebounding over heads and potentially out of court.

  6. hoopster216 — November 17, 2010 @ 10:20 pm

    I have to remember to bring my slide rule with me to practice next time…

  7. Anthony — August 20, 2012 @ 12:48 pm

    Sorry Dale, your belief is wrong. 2 basketballs will fit in the hoop at the same time despite your calculations.

  8. Christopher Corbett — January 1, 2016 @ 8:30 pm

    2 balls do not fit thru the hoop at the same time. I tried it with two regulation balls. They don’t fit. Simple math also indicates they do not. Here is a pic of me debunking this myth. http://www.austinyouthbasketball.com/do-2-basketballs-fit-thru-the-rim-at-the-same-time/

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