Science Fair 2015

By: James Pietrowiak

How does an angle of a basketball shot effect the percentage of shots made?


It is something that every basketball player or fan wonders, how does the angle of the shot effect the outcome of the shot? I am no different because basketball is something that interests me in many different ways because I am a huge fan and an avid player. I have always wondered if the angle really does have a large effect on the outcome. I plan to test this and see if the angle of a shot in fact has an effect on the outcome of a shot.

The basic facts that we will need to know are: a men's basketball measures 9.5 inches in diameter. The rims have a diameter of 18 inches, and if you were to drop a basketball from straight above the rim at a 90 degree angle there would be 4.5 inches of space between the ball and the rim when it goes through. Nobody shoots straight up in the air so we need to figure out what angle gives you the greatest chance for that sweet feeling of a “nothing but net” shot.

The higher someone is to release a ball the more the elbow must move upwards and this gives the ball a greater angle. This is exactly what I am looking for, that is why I decided to make it easy for my participants by giving them three checkpoints for them to release the ball from chest, chin, and overhead. This ensures that they must put a larger arch on the ball, we will record the percentage of shots made and see if there is a correlation between the amount of shots made and the angle they were taken from.

There are many variables that can change the outcome of a shot, two of which are temperature and wind. The temperature and wind can have a large effect on a shot but we will not have to worry about this because we will test in a climate controlled area. We will also have an exact distance for each participant to shot from. We will have each person shoot from the free throw line which is 15 feet away from the rim.

Every person has a different way of shooting which impacts the release of their shot. So we will use a large group of people to make sure a person that is used to shooting from the chest or chin or over the head does not mess up the evidence and data just because that’s the way they are used to shooting. We will also use people that are of the same skill level. We will use players that are on the high school freshmen basketball team at Coppell High School. This will give us more dependable evidence that is easier to compare because they are all closer to the same skill set.

The variable that we will change is where each person will release the shot from, which will change the angle of each shot. We will have each person shoot from their chest, chin, and from over their head. We will have them shoot 10 shots from each position for 3 days. This will help get a more exact percentage of shots made and allow us to compare all three positions to each other, so we can see what we come up with for the preferred shooting angle or release that provides the best opportunity for a make. This is what will answer the question that we are asking in the first place. The data will provide evidence in proving what the best angle to shoot from is.

There are many different ways to test the trajectory of a shot but the way I am designing the experiment is such that it is easy for everyone to understand. It should not confuse the person looking back at the results of the experiment. I am hoping to simplify the way of explaining a complicated topic involving trajectory and parabolas and how it affects the arch of a basketball.

The long lasting question of if the trajectory of a basketball shot has an affect on the outcome of the shot is something that I am hoping to shed some light on because it would affect how people play basketball and would affect how people practice and how they view a game and a persons shot. I feel like in sports people over look what is happening in front of their eyes scientifically people just watch and cheer and do not have a second thought about what just happened. But I think it is time that people start to look at it because it can give you an upper hand on everyone else because you know what to look for. This project will not just show what is the best angle to shoot at but how it is important to start to look at sports in a more scientific way, as we have done with many other areas of our life.


I believe that in this lab that the chin will be the best way to shoot a basketball because it will be the best angle when it is still easy to get the ball to the basket without using all of your strength.


  • Mens size basketball (29.5)

  • Measuring tape

  • Basketball hoop and court (Coppell YMCA)

  • Volunteer shooters


  1. Go to Coppell YMCA

  2. Take shooters and teach them how to shoot from each check point. (chest, chin, and over head)

  3. Measure 15 feet from rim and mark that point.

  4. Have each person shoot from each check point 10 times and record percentage made.

  5. repeat this for the next three days.

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Statistical analysis

This graph displays the averages from all 5 people who participated in this experiment. The bar graph makes it easy to find and compare the percentage of makes from each check point. This proves that there is a positive correlation between the a higher arching shot and the percentage of shots made. Clearly shown in the graph you can see that every persons highest shooting percentage was when they had the highest arch on the ball when shooting. The only conclusion that can be drawn is that you shoot at a higher percentage and more efficiently when you have a higher arch and release the ball over your head.


Dependent variable- The percentage of shots made.

Independent variable- The angle in which shooting from.

Control- The angle in which each person shot from.

Experimental group- The participants shooting the free throws.

Factors that were held constant- The distance in which each shot was taken from (15 feet), and the size of the ball used (29.5).


The results of my experiment did not coincide with my hypothesis I stated that I believed that the best angle would be to shoot from the chest but in fact the best angle was to shoot from above your head. The purpose of the experiment was achieved through the results because we know that there is a correlation between percentage of makes and the arch put on the ball. This is something that many have ponder for awhile and is now answered through this.

Sources of Error

Basketball is a sport when people can step on the floor one day and never miss and the next never make a shot. This is the biggest aspect that can give my results small amounts of unreliability because if all of the people just were on fire and could not miss it would give me erratic results and that is why I spaced them out over 3 days so I can try not to experience that result.


I could improve this experiment by having a larger sample size of people to test on as well I can spread the days out over a longer period of time to get more exact results that are more credible and can be trusted. I would also make sure and see if one can emulate the same percentages from a lower angle as well and see how rare it is.


This experiment can help many people who play the sport of basketball because if they are an unreliable shooter you can help yourself by increasing the amount of arch you put on a shot. Many players have the problem of a “flat shot” which is a lower angle and it has a small chance of going in. We now have proof that shooting with a higher arch can help your shot and many would change how they shoot for the better.