Science Buddies: "Ask an Expert"

How does the air pressure affect the soccer ball when kicked?(main science subject question)
How much air should a soccer ball usually have?
What is a psi?
How can I take air out of a soccer ball? ( please!)

Hi,

Have you checked out the Science Buddies Project write up on soccer ball pressure?

https://www.sciencebuddies.org/science- ... p007.shtml


Here is an answer to the soccer ball pressure question:

http://www.bigsoccer.com/forum/showthread.php?t=75483

Here is a science fair abstract on soccer ball pressure:

http://www.usc.edu/CSSF/History/2005/Projects/J0203.pdf

I hope this helps you set up your project.

Best wishes and above all, have fun with it!

Barrett Tomlinson

What is a psi?

If you put "What is PSI?" into a search engine like ask.com, you should get your answer.

How can I take air out of a soccer ball?

You need to find an "inflation needle". These typically come with new soccer balls (and other inflatable balls like basket balls and American foot balls). Be sure to wet the needle before inserting it into the air inlet in the soccer ball.

Why doesn't the soccer ball go far when the soccer ball
has less air than usual?

P.S. Thank you for answering my other questions!

dear bluestone,

Thank you for contacting science buddies. Regarding your question, I think that the more air that a soccer ball has the less dense it is. The decrease in density allows the ball to travel more with the air/wind. The less air a soccer ball has the more dense the object is (a lot more dense than air) so the soccer ball will not go through the air/wind easily unless you apply force (kicking or throwing the ball) to overcome the density difference. I don't know if you know about density or not, but here is a link to a website that will explain it http://en.wikipedia.org/wiki/Density I will try to give you an explaination about density: Molecules are what make up things. They are groups of atoms, which are the basic units of matter. The more close together the molecules are in something the more dense an object is. Gases, such as air, have molecules that are far apart, so they are less dense than solid objects, such as a soccer ball. If you are having trouble understanding density you should ask your science teacher at school. hope this helps and if you have any more questions post them

good luck,
scienceexpert123

I think that the more air that a soccer ball has the less dense it is.

Excuse me but the more air a ball contains, the heavier it will be, so it should be denser because the diameter will not increase as fast as the mass of the air inside.

There are actually multiple force interactions involved. There are many references that you can search to find your answers. A couple of major points:

1) The elasticity of the surface of the ball changes with the internal pressure. The higher the pressure inside, the faster the ball will return to its original shape after the kick so the more initial velocity that will be imparted to the ball by the same kick.

2) A heavier object traveling at the same speed will have more momentum and take more force to slow it down.

There are other factors as well so do some searching and reading. Putting "How does air pressure affect a soccer ball?" into something like ask.com will give you some great articles.

bluestone,

I have merged your two topics together into one. Please keep all questions about your project on a single topic; this helps the Experts keep track of your project and so helps them be able to better help you.

Thank you.

Why does a soccer ball go farther when it is fuller?

This question is best answered by the Newton's 3rd law of motion. When you kick a full ball, the force exerted is not absorbed by the elasticity of the ball, but hits a hard surface, better transferring the force in your kick (equal and opposite force). See the following link to understand it better:

http://csep10.phys.utk.edu/astr161/lect ... 3laws.html

Good luck!
Teresa

How can I get better at soccer so I can get accepted into the diplomats? Ok so my friend got offered a chance on the Islands best team. The ALL-STARS. I have never seen her play before but that must mean shes good. I want to prove myself to everyone who has been on that team. Soccer is like most of my life and I play age level soccer, but I want to get better and I need some tips on how to be better.

Hi,

We're scientists, not soccer players, so we are probably the wrong ones to ask about this--but I assume that the way to get better at soccer is the same way to get better at anything else: practice, practice, practice. My brother, who's now a professional musician, used to practice at least 30 minutes per day every day.