When students enter my classroom, one of the first things they notice and want to explore is the Flying Pig that I always leave hanging from my ceiling. Of all the equipment in my room, the Flying Pig is one of my favorites because it accomplishes so much in such a small and economical space. Although a simple device, the Flying Pig can be used throughout the entire year and helps to build so many deep connections to everything we teach.
In my 12 years in education, I have taught conceptual physics, New York State Regents Physics, Concurrent Enrollment Algebra-Based Physics, Calculus-Based Mechanics, Astronomy, Chemistry, and Co-Taught Earth Science. While the Flying Pig is typically used around the time physics teachers talk about centripetal forces, the Flying Pig is an extremely versatile piece of equipment that can be utilized in a variety of units and subject
areas. In every class I’ve taught, the Flying Pig has made an appearance at least once! In what follows, I would like to share some of the times that my Flying Pig has made an appearance/connection in my classroom.
In my 12 years in education, I have taught conceptual physics, New York State Regents Physics, Concurrent Enrollment Algebra-Based Physics, Calculus-Based Mechanics, Astronomy, Chemistry, and Co-Taught Earth Science. While the Flying Pig is typically used around the time physics teachers talk about centripetal forces, the Flying Pig is an extremely versatile piece of equipment that can be utilized in a variety of units and subject
areas. In every class I’ve taught, the Flying Pig has made an appearance at least once! In what follows, I would like to share some of the times that my Flying Pig has made an appearance/connection in my classroom.
New York State Regents Chemistry
Yes! The Flying Pig absolutely has a place in the Chemistry classroom. In addition to adding a bit of whimsy to your room, I used the Flying Pig when talking about models of the atom and atomic trends. When teaching the history of the atomic model, the Flying Pig is a perfect supplement to illustrating the Rutherford Model of the Atom and adding a contrast point when moving to the Bohr Model of the atom.
In Rutherford’s model of the atom, electrons orbit the nucleus much like planets orbit the sun. The Flying Pig can be used to represent an electron, with the force of gravity acting as the analogous force of attraction between the electron and the nucleus. Rutherford’s model failed to predict the stability of electrons in their orbit, as the accelerating electrons should emit light, causing them to eventually crash into the nucleus. Likewise, the issues with the Rutherford model can be modeled with the Flying Pig by simply turning off the motor of the pig and letting friction act as the analogy, which will cause the pig’s orbit to decay into the center of the nucleus.
I also used the Flying Pig when teaching atomic trends in the periodic table of the elements. When looking across rows in the periodic table, atomic radii get smaller due to the increased electric force between additional protons on the electrons. This can be modeled with the Flying Pig by taping a small mass to the pig. As we previously connected, the Flying Pig represents the nucleus. By adding some additional protons (modeled with something like a 200g or 300g mass taped to the pig’s stomach), the pig will now orbit at a noticeably smaller radius.
Earth Science and Astronomy
It is all about orbits for the Earth Science and Astronomy class! Whether it is Kepler’s Laws, Newton’s Law of Universal Gravitiation, or just simply talking about the planets and the sun, the Flying Pig is so useful to always have hanging in the room to provide a direct connection to your students.
If we model the Flying Pig as a planet and the force of gravity as coming from the sun, we can use the Flying Pig to illustrate all three of Kepler’s Laws of Motion. Through observation or analysis, the Pig can be shown to move in an elliptical orbit (with a very small eccentricity), sweep out equal areas in each interval of its motion, and one could even tie the string to be shorter and show how that results in a shorter period to help bring intuition to Kepler’s 3rd Law.
In Astronomy, you can also use the Pig to talk about orbits and conic sections (circles, ellipses, parabolas, and hyperbolas, i.e., all the possible types of motion given a central force). Give the pig a little push and a little speed with the wings off, and it moves in a little circle. Ask your students, “What would the pig have to do to move to a larger orbit?” (Bigger push=more speed). A really fun question to explore with your class is the Hohmann Transfer. Have the Pig flapping and ask your class, “How would I have to push on the pig to move it to a larger orbit?” It makes for a really fun experiment to have the kids try pushing on the pig in different ways to learn that thrust, i.e., simply speeding up the pig, is all that is needed to transfer to a larger orbital radius.
Conceptual Physics
For me, Conceptual Physics is all about thinking about physics, with very little math in the class due to the prerequisites of the course. The Flying Pig is my main tool I use when I talk about centripetal forces. Here are some open questions I ask that we explore as a class:
● Why does the Pig move in a circle?
● What would happen if we cut the string?
● Is the pig accelerating?
I find the biggest hurdle is teaching that centripetal forces are not “new” forces, that anything can act as a centripetal force if an object is moving in a circle. I always try to teach Newton’s 1st Law as “An object will move at a constant velocity unless unbalanced forces act on it.” The Flying Pig is perfect for this model because something has to be happening for its velocity/momentum to be continuously changing. The Flying Pig is also a great tool to utilize in the Energy unit when modeling energy transfer. Some ideas to incorporate are:
● “Where does the Flying Pig get its Kinetic Energy from?”
● “Draw an Energy Bar Chart of the Pig while being held stationary at an angle and while moving.”
New York State Regents Physics or High School Physics
In addition to everything described in conceptual physics, there are some additional things I do with the Flying Pig in a slightly more advanced class that utilizes more math.
I first use the Flying Pig in this class when teaching kinematics at the beginning of the year. A very simple, short experiment is to ask, How fast is the pig moving? I enjoy doing this as an open whiteboard experiment, because I notice that when I merely tell students about the kinematics of circular motion, they tend to forget that the distance the pig moves is the circumference of the circle it traverses. When presented as a more open-ended experiment, the students can reason it out themselves, and that has tended to result in deeper understanding and longer-lasting impact.
A great follow-up to this lab is to ask, “OK, now how fast are WE moving? (I’ll leave it up to you and your reference frame to decide how deep you want to go down the rabbit hole with this one, but I usually stop with the approximate speed of our sun orbiting the Milky Way).
One of the most important parts of teaching this level of physics is teaching the balanced vs. unbalanced forces models and their corresponding motion. In addition to everything I do in conceptual physics with the pig, a great additional use of the pig is to use it as an accelerometer. One of my favorite balanced vs. unbalanced forces problems is modeling the motion of a sprinter during a 100m dash or a car driving a mile as fast as it can go. It is a great way to combine the models of balanced and unbalanced forces, along with the corresponding motion graphs. By simply holding the pig from the string while you speed up, slow down, and walk at a constant speed, you can help students build a deeper intuition of Newton’s 2nd Law.
Concurrent Enrollment Algebra-Based Physics and AP Physics 1
In addition to what I teach in Conceptual and Regents Physics, here are some additional connections I make it this level while using the Flying Pig: civil engineering and the safe speed to go around a turn, artificial gravity and the design of amusement park rides like the Gravitron Ride (spinning UFO disk ride), and fighter pilot training.
Civil Engineering:
Just like how our pig “knows” what speed to travel safely in its circle, civil engineers place yellow signs to give the recommended speed to go around a curve. I start this activity by using the exact lab provided by Arbor Science (see the PDF of the lab here, along with the corresponding teacher notes here) to teach about centripetal forces and tension. Side note: This is a great lab that I think is perfect at this level because of how it connects kinematics, free-body diagrams, and centripetal forces.
The follow-up I do on the next day is to have students use Google Maps to find a curve that they can also see real-life pictures of by dropping the “little man” on the road. We then calculate what the sign should say by saying that friction must be acting on the centripetal force, pulling the car around the curve (if a student asks why it’s friction, ask what would happen if the curve were covered in ice!). By using something like MS Paint or anything that can make a circle, you can fit a circle to the curve and measure the radius of the curve. You then have to assume a coefficient of friction, which leads to a great talk about engineering (should an engineer choose a coefficient for the best possible conditions, like a hot and dry day, or the worst possible conditions. In upstate NY, where I teach, I use μ=0.2 as that seems to approximate our road signs for rubber on an icy road. This is a phun way to connect our classic pig experiment with a real-life calculation.
The next follow-up in the AP Physics 1 class would be to talk about banked curves. I like doing this activity right after the classic pig lab because, just like how the mass term cancels out when you solve for the equation of motion for the pig, an extremely similar line of thought is used for the banked curves equation. This allows for natural scaffolding that makes the banked curve problem substantially more approachable.
Artificial Gravity and G-Forces:
I always like to ask my class, “What do you think the pig feels while spinning in its circle?” The Flying Pig is the perfect tool to have on hand when talking about artificial gravity (like in the Gravitron Ride at fairs or as heavily discussed in the book/upcoming movie Project Hail Mary by Andy Weir). Calculate the centripetal acceleration of your pig after performing the provided lab, and then ask some questions like:
● How fast would the pig have to move to produce a gravity of 1-g?
● Calculate the centripetal acceleration of a ride using data from a video and compare it to the Pig's and Earth’s gravity.
● What would happen if a fighter pilot took a turn with too small a radius of curvature? (This is called G-Lock and happens when the g-forces are so high that a person blacks out. There are a lot of really cool biology connections here, as everyone has a different tolerance of g-forces, as well as things like how using breathing techniques and a pressurized G-suit can help a pilot handle larger accelerations.
● Talk about astronauts and centrifuges used for training. Our little pig is like its own little centrifuge.
AP Physics C: Mechanics
In addition to everything previously discussed in the Algebra-Based Physics course, there are a few additional places where the Flying Pig can be utilized in the Calculus-Based Mechanics class.
I will additionally use the Flying Pig in my Simple Harmonic Motion Unit because the Flying Pig is a conical pendulum. As is done in the course, the small angle approximation is used to classically show that a simple pendulum is not true simple harmonic motion, but is simple harmonic motion in the case of small angles (I always say less than 30° because all things considered it gives less than a ~5% error). Likewise, we can use the small-angle approximation on the Flying Pig and see how the measured period of the pig compares with the theoretical period of a simple pendulum.
Instead of doing the classic Flying Pig Lab (linked again here), I prefer to ask the students to predict the period of the Flying Pig, starting with a free-body diagram. Finally, at this level, it is great to see when a model breaks down and why. In the Flying Pig lab, the mass terms in the derived equations cancel out, showing that mass should have no effect on the period and angle of the pig. In experimentation, though, we see that the pig does, in fact, travel in a circle with a smaller angle (and the same period) when something as small as 1 pig mass (approx. 200-300g) is added to it. This is because the motor has a fixed power output, so the pig is no longer able to maintain the same angular velocity.
In Summary
When I try to allocate my very modest budget to buy supplies, I always try to find that sweet spot for an item that can [1] accomplish a lot of physics, [2] doesn’t break the piggy bank, and [3] is durable enough for kids to play with. The Flying Pig accomplishes all three. I’ve kept the same Flying Pig hanging in my room for the past seven years for hundreds of kids to come in and send it flying. Whether it is just a single pig hanging in your room or a whole class set to use for lab activities, I feel like the Flying Pig is on the list of essential items that should be found in every physics classroom. Finally, by leaving at least one pig up in your room, you add some phun and whimsy to your class, and it becomes one small additional thing to help create an inviting, growth mindset in your class where students feel comfortable experimenting, asking questions, and getting comfortable with being uncomfortable. Just like how we can learn about anything in the physics and science classroom, we always like to say, “When Pigs Fly…Fisikz is Phun!”
About the Author
Anthony Canestaro is a Physics and Astronomy teacher at Cortland High School in Cortland, NY. He is an emeritus of the NYS Master Teacher Program and the NASA Astronomy Activation Ambassadors Program and was previously an ambassador for STEP UP.
His favorite area of personal interest is Cosmology, specifically Dark Energy and the Cosmological Constant Problem. As a teacher, his favorite things to teach about are Waves, Sound, and Optics, but it always seems that every lab he does is his “absolute favorite one we do all year!”
His interest in physics began with conversations at the dinner table with his pop asking questions like “what’s the speed of a shadow?” Nowadays, his favorite thing about teaching physics is helping students discover the “pleasure of finding things out.”
