Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


The Physics of Field hockey Friction

No description

Emily O'Brien :)

on 8 January 2013

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of The Physics of Field hockey Friction

Why Did I choose this topic?!? The Physics of Field Hockey By Emily O'Brien #1 Background Information... What is field hockey?! field hockey |fil(d) hki|
A game played between two teams of eleven players who use hooked sticks to drive a small hard ball toward goals at opposite ends of a field. What does the field look like? What do you need to play? Stick and a ball Proper protection Field Hockey Field Grass Turf or Goal and most importantly... A Spectacular Team ! Because I play Field hockey! That's Me and it is fun! The Field Differences Here at CVU, all of the athletic fields are made of pure natural grass... Where as at other schools and majority of colleges, they have the luxury of being able to play on turf. Why does it matter? I'm sure that everybody is aware that the surface of which the sport is played is very important. Whether it be mud, grass, water, or turf all of these elements can change the game drastically. Generally, on most occasions people prefer to play sports on turf. Not to mention although expensive, turf fields require much less maintenance. How does this relate to physics?!? What will I be investigating? While playing field hockey throughout the years, my teammates and I have noticed the difference between playing on turf and grass. When playing on turf, it is a completely different game. Generally, on turf the game is much faster paced. The ball is much easier to accelerate and travels much faster even with the slightest tap, where as on grass in order to move the ball you must use a large amount of force or a very strong hit. Generally playing on turf involves much more running and is much more tiring. Majority of the time, the team with more experience playing on turf rather than grass has the advantage. But we have always wondered why this is. It is for this reason that I have decided to look into the physics of fieldhockey. How does the surface on which you play field hockey (Turf, grass, gym floor, pavement etc.) affect the distance the ball is able to travel once it has been hit? What application or law applies to this project?! Friction is an example of a contact force Different types of Friction.. What is Friction? F R I C T I O N friction |frikSHən|
The resistance that one surface or object encounters when moving over another
The action of one surface or object rubbing against another In other words: Friction is the resistance of motion Contact force:
In physics, a contact force is a force between two objects (or an object and a surface) that are in contact with each other. How does this relate to field hockey? The two interacting objects would be the ball and the surface at which it has contact with. (ex. grass or turf) Static Kinetic static |statik|
1 lacking in movement, action, or change kinetic |kənetik|
of, relating to, or resulting from motion. How does it relate to field hockey? Once the ball is hit the force at which the field hockey stick hits the ball, is what will be driving the ball forward. However at the same time the friction created between the ball and ground will be acting against the ball this eventually getting to stop. Don't forget, we must also factor in that the gravity is working to force the ball toward the ground, thus also increasing friction. Hypothesis.. Sadly, the outcome of my experiment did not match what the physics was supposed to support. My hypothesis going into this experiment was that the ball would travel much faster on turf than it would on grass due to their being less friction on the turf. However... Because it was the middle of winter, and we have no grass showing outside, I had to alter my experiment. My Experiment For my experiment because I can not calculate the friction of grass, I had to switch my plans altogether. I used the carpet in my house to represent the grass, and the concrete basement to represent turf. Experiment Calculations In my experiment in order to find friction I would first need to find the following variables:
Initial Velocity
Final Velocity
Normal Force
And Finally Coefficient of friction I would then need to solve for these variables two times, once using the carpet and once using the cement. Here is how I was able to solve for each variable through out the experiment in order to find the coefficient of friction
Vi= 0 (The ball starts at rest before hit, therefore v=0)
t= the time it took for the ball to come to a rest
Vf= solved for using the equation d= 1/2 (v+v0)t
d= distance the ball traveled in meters
a= acceleration, calculated using the equation V=v0 + at
m= the mass of the ball weighed in kg
F= Force calculated using equation F=m*a
N= Normal Force, calculated using N= M*g
u= co efficient of friction, calculated using F=u N Solving for Variables My Calculations... d= 1/2 (v+V0) t V=V0+ at F=m*a NF= m*g F= u N
My final calculated coefficients of friction were:
Carpet: .0214
Cement floor: .0224 In Conclusion... However this experiment was a bust. Because the lower the number for the coefficient of friction, means the smoother the surface. Because the lower number of the two belonged to the carpet, this does not make sense because realistically, there is no way that a carpet could have less friction then smooth cement given the circumstances. The results from this experiment would indicate that the field hockey ball would move faster on grass than on turf, which is obviously inaccurate, therefore this was a fail of an experiment :( Some Possible Sources of Error: Incorrect measurements of any sort
Incorrect conversions at any point
Incorrect calculations at any part
Glitches with stop watch or calculator
Of course, the experiment was not actually done on the proper surface, so had it been done on turf and grass the coefficient of friction would have been much much different, hopefully the coefficient of friction for the grass would have been a much greater number than that of the turf field. So, although my results did not reflect the physics behind this experiment, at least you now know a bunch of new things about the relationship between field hockey, physics, and friction ;) remember physics is F= U N. The Equation for Friction: F= u N Force Coefficient of Friction Normal force ~Normally our weight
~N= m* g ~Depends on the material
~ A number between 0 and 1 ~F= m*a Friction is measured using using the variable for coefficient of friction. It is an indicator of how smooth the surface of something is. The coefficient of friction is always a number between 0 and 1. Generally, the lower the number, the smoother the surface is. For example a coefficient close to 0 is very slippery like ice, and a coefficient close to 1 is rough like sandpaper. Coefficient of Friction: The End
Full transcript