Road Runner Physics

These clips from Warner Brothers Road Runner cartoons are intended for use by physics teachers. Info and suggestions for use are included next to each clip. It is recommended that you download and archive the clips that you would like to use. To do this, right click on the clip and select “Save Video As…”. On a Mac, try control-click. The posting of theses video clips for educational purposes conforms with the fair use provisions of the copyright act. At the bottom is a PowerPoint file and suggestions for classroom use of the clips.

Introduction (1:01) – This opening clip will help introduce your students to the Road Runner (Accelleratii Incredibus) and his perpetually hungry nemesis, Coyote (Carnivorous Vulgaris). Doesn’t ACME sell coyote food?


Fan-Powered Balloon with Anvil (1:03) – This clip is rich with physics. Contrast the fan power to the fan powered sail clip. How should the balloon respond when the 500 lb anvil drops? When it rises rapidly? What object should hit the ground first?


Rolling Boulder (0:11) – Does the outcome obey conservation of energy? Is the path of the boulder after leaving the cliff realistic?


Fan Powered Sail (0:35) – Could this propulsion scheme work? Does it follow Newton’s 3rd Law? Would adding a sail to a propeller powered car work? Compare to the fan-powered balloon. Why couldn’t Coyote make the turn?


Giant Rubber Band (0:21) – Compare the force required to stretch the rubber band to that required to move the boulders. What is the ultimate source of this force? Is momentum conserved in the end?


Human Cannonball (0:18) – Blatant violation of Conservation of Momentum. It is similar to the Spring Punch clip. Could something like this appear to happen? Maybe if Coyote was made of neutron star material.


Log Tunnel (0:28) – Good static equilibrium demonstration. Strong evidence that Road Runner has much less mass than Coyote. One Road Runner couldn’t possibly nourish one Coyote.


Outboard Motor (0:51) – This clip is similar to the fan-powered sail. It ends with the Coyote going off yet another cliff. His path is horizontal until he comes to a stop. If only he wouldn’t look down! A colleague calls the horizontal part the NFD, No Falling Distance. Many of your students have the misconception that the NFD increases with initial speed.


Pendulum (0:21) – Although Coyote gives the pendulum a small push, this is still a clear violation of Conservation of Energy. How does Road Runner know exactly where to stop?


Rock Fall (0:34) – Demonstration of the importance of knowing where the Center of Gravity is located. Good use of plumb bob and telescope is wasted.


Spring Launch (0:26) – The Coyote is thwarted by poor design this time. What could be the spring constant if the Coyote is able to compress it by pushing horizontally?


Spring Punch (0:18) – This one is similar to the Human Cannonball clip. Momentum is definitely not conserved.


Powerpoint File – I have heard from many teachers that find these Road Runner cartoon clips useful in class. I use them on the first day of physics class. Sometimes we focus too much on what students don’t know about physics instead of what they do know. I believe one reason people find humor in Road Runner cartoons is they see things that violate the laws of physics. With a little prompting, students can display a deep knowledge of many physics principles. I like to give them evidence on day one that they already know a lot about physics. We can build on that during the course. I show the slides posted for download at left. If you want to use them, you will need to insert the clips after you download them. I list the ones I use in the notes on each slide. The first question asks them “What eats roadrunners?” Invariably they answer “coyotes”. The Coyote never catches Road Runner in the cartoon world. Coyotes don’t eat roadrunners in the real world too. Animals that do prey on roadrunners are listed on the last slide. Is this a trick question? Many people think so. However, most students know the coyote never eats the Road Runner, they just didn’t think before they answered. Another good lesson for a physics class. Note: Road Runner is the cartoon bird, roadrunners are the birds found in nature.