As for the rest of your statement I'm sure there's deep meaning in there somewhere, but I can't follow it enough to find it. Basically stated this in my own words: This suggests that a disc thrown with more spin will have less precession, but all discs will precess. Therefore, if one were to simply throw a flying disc, the lift would also cause a moment on the disc and cause it to flip over backwards.
The key to the stability of the flying disc is its spin. The spin of the disc results in gyroscopic stability or pitch stiffness, and the greater the speed, the greater the stability. Typically the moment due to lift and drag pressure on the disc is nearly perpendicular to the angular momentum of the spinning disc, and thus the disc experiences gyroscopic precession.
This precession causes the disc to wobble as a gyroscope wobbles when its axis of spin is perturbed from the direction of gravity. Likewise, by spinning the disc, one trades roll stability for pitch stiffness. It is also worth noting that the viscous no-slip condition at the boundary of the spinning disc causes the disc to generate some degree of vorticity.
The circulation about the disc and the free-stream flow of air past the disc causes a force in the direction of the cross product of V with the angular momentum of the disc. This is attributed to the Magnus Effect, which is caused by one side of the disc percieving a higher free-stream velocity than the other, causing a pressure gradient.
This will cause a flying disc thrown clockwise to veer to the left, which is particularly noticable as the viscous effects become more pronounced at the end of the flight.
It is this same effect that causes a ping pong ball to travel along a curved path when a skilled player puts spin on it with the paddle. The Disk Rim The thick rim at the edge of flying disc serves multiple important purposes. First and foremost, the thick rim eases gripping and tossing the disc. Without the thick rim, throwing a flying disc would be significantly more difficult. Additionally, the thick rim significantly increases the moment of inertia of the disc about the axis of symmetry, enhancing the stability of the disc.
A flat plate without a thick rim, such as a dinner plate, has much less stability than a typical flying disc. Finally, the cupped region on the bottom of the disc substantially increases the coefficent of drag from the vertical profile, while the horizonal profile is still somewhat streamlined. As a result, as the disc begins to fall, the cupped profile behaves like a parachute, and the horizontal component of drag dwarfs the vertical component. This allows the flying disc to be thrown much further than a ball of equivalent velocity.
Interesting to note, however Hummel which is a source of the author stated that the Magnus Effect is practically negligible and their tests were done using an Ultrastar Lid which has a much larger sidewall than most golf discs and much less gyroscopic because the rim thickness is practically uniform to the flight plate thickness.
The Magnus Effect would have much less effect on a high speed driver. So while the Magnus Effect becomes more pronounced at the end of the flight, it can be concluded it has little to do with the disc fading. Often considerable influence on the aerodynamics of the Frisbee has been mistakenly attributed to the effect of the spin about the axis of symmetry. Consider the motion of the left and right sides of a Frisbee due to spin in a right hand backhand throw rotating clockwise viewed from above.
The motion of the left side of the Frisbee viewed from behind is in the direction of the velocity while that of the right side opposes velocity. Consequently the total velocity on the left due to spin and linear velocity of the COM will be greater than that on the right.
Since lift is quadratic in velocity, the distribution of the lift might consequently be thought to be greater on the left side than the right side. The COP would be expected to shift left of the midline of the disc to the side with the higher velocity. Such a shift would cause a positive roll moment. However, data collected shows the roll moment to be negative, not positive. Thus the mistaken rationale presented above does not even calculate the sign of the rolling moment, much less its magnitude.
Also, it is important to understand that in the lift calculation, CL applies only to the Frisbee as a whole and the relative velocity must be the velocity of the COM, not a left or right side velocity.
In any case, the roll moment is very small and does not play a large role in the flight dynamics. As the Bernoulli equation predicts an upward force due to the increased flow velocity over the top of the Frisbee, the differential velocity across the disc results in a side force generated to the right. This side force is called the Robins-Magnus force. It is observed in the curved trajectories of soccer balls and baseballs, where spin has been imparted.
However, for a Frisbee the resultant side force is near zero, and has been neglected in the equations of motion. You realize that Scodary paper is just a homework assignment for a freshman level physics class, right?
Where do you get your info? It says Coursework, not homework assignment. If that is just a homework assignment, then holy crap! K, PY is somewhat more advanced than freshman level different colleges with their different numbering systems blah. Looks like he was taking it his senior year for his BS in Physics.
It's still a very weak homework assignment or coursework, but it's not a thesis or a semester project by any means. It's just a very brief summary of four sources. That doesn't mean everything I did in college was great it doesn't mean anything I did after college was great, either. I turned in a few crappy papers in my day that I wouldn't want you to use as evidence of anything. The "force" effectively acts on the right side - so the effect "pulls" the disc to the left.
The "Force" is pushing direction against the side-wall - Side-force into the right side. The "Effect" is pulling direction to the left.
If the COM is not centered at the geometric center height of the side-wall, this will cause a rolling moment which has nothing to do with spin. In frisbees this "force" or effect is mostly negligible, but to a small degree notable. Rhbh clockwise the pressure on the left would be higher causing it to veer right. Think looking down the line of a golf ball just hit with backspin and tilting its rotational axis 90 degrees clockwise. I didn't study at MIT or have an engineering masters yet, just graduated high school but that would be my logic.
Instead of thinking of it as a drag force on the left think of it as a sideways plane lift force on the left. I also believe this has an influence on beat discs turning more. A, NGSS.
C, CCRA. Join us in Wonderopolis tomorrow for a closer look at how technology affects how we perceive reality! Did this Wonder of the Day leave you flying high? Ask a friend or family member to help you check out the following activities:. Hi again, Live! Glad you came back to check this one out. Thanks for sharing that you liked it! We hope so, Shanna! It can be tricky to throw but keep at it. You'll get the hang of it! We are undergoing some spring clearing site maintenance and need to temporarily disable the commenting feature.
Thanks for your patience. Drag a word to its definition. You have answered 0 of 3 questions correctly and your score is:. Want to add a little wonder to your website? Help spread the wonder of families learning together.
We sent you SMS, for complete subscription please reply. Follow Twitter Instagram Facebook. How does a Frisbee fly? Who invented the Frisbee? What is lift? Wonder What's Next? Ask a friend or family member to help you check out the following activities: Do you have a Frisbee? We hope so! Frisbees are fun to play with, especially with a friend or family member. If you don't already have one, see if you can borrow one from a friend or neighbor or purchase one from a store.
Then get outside and have some fun tossing the Frisbee with a friend! Frisbees can be used for more than just a fun pastime. They can teach you about science, too! In this fun activity, you'll explore how the tilt of a Frisbee affects how far and in which direction it flies.
Have fun! Have you ever played Ultimate Frisbee? It's a fun game that's like a combination of several other sports…all played with a Frisbee! Check out What Is Ultimate? Read through the rules and organize a game with your friends! Did you get it? Do not sell my personal information. Cookie Settings Accept. Manage consent. Close Privacy Overview This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website.
We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience. Necessary Necessary. Necessary cookies are absolutely essential for the website to function properly.
These cookies ensure basic functionalities and security features of the website, anonymously. The cookie is used to store the user consent for the cookies in the category "Analytics". The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is used to store the user consent for the cookies in the category "Other. The cookie is used to store the user consent for the cookies in the category "Performance".
It does not store any personal data. Functional Functional. Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
0コメント