Why It's Impossible to Throw a Perfect Spiral (ft. Tom Brady) - our latest video, ad-free!
Added 2025-06-02 10:29:07 +0000 UTCEven the GOAT Tom Brady can’t throw a perfect spiral.
Comments
That’s a great question. The same mechanism we used to explain the football's path was described over a century ago for artillery shells. In fact, a 1920 paper outlines similar behavior: how a spinning projectile tends to align with its velocity vector, what causes the torque behind that alignment, and why right-handed spin can lead to a slight drift to the right. Now the effect does depend on matching the wobble rate (caused by precession) to the rate the trajectory curves downward—something that varies with launch angle, velocity, and spin rate. So for different bullets I'm not sure exactly how much this effect comes into play, but if you’re curious, I’d recommend looking into the original paper: Fowler, R.H.; Gallop, E.G.; Lock, C.N.H.; Richmond, H.W. "The Aerodynamics of a Spinning Shell." Philosophical Transactions of the Royal Society of London, 1920, 98, 199–205. Thanks - Henry, Writer for this Video
Veritasium
2025-06-09 09:39:03 +0000 UTCWhen I described to my brother Gary how footballs in airflow are very different from spears in the details, he immediately asked, "Aren't bullets more like footballs than spears?" Good question! Shoot a bullet straight up and it's harmless. Shoot it at 45 degrees and you can kill someone miles away because the bullet remains "ballistic" -- meaning it must do _exactly that these footballs are doing" by reorienting their spins as they arc first up and then down. While your video thoroughly addresses the role of spin in stabilizing bullets, I don't recall any explicit follow-up after the football explanation to how the same reorientation effect also makes bullets more dangerous on "football pass" trajectories. The higher speed of the bullets makes it less intuitive. Also, do bullets necessarily have wobbles to work correctly? Does the spin similarly introduce a right or left bias? Does the need for wobbles affect bullet design? Could bullets be made more accurate by designing them explicitly for wobble effects?
Terry Bollinger
2025-06-04 19:30:54 +0000 UTCGlad you enjoyed even as a non-football fan, that's great to hear!
Veritasium
2025-06-03 08:54:35 +0000 UTCYou harnessed a lot of obscure tech for this and plumbed the depths of the topic. But you asked even MORE questions! — Waiting for the two-hour version (and I’m not even a follower of professional football). Tom Brady seems like a very nice and gracious man. (Loved it when he broke the plexiglass!)
Timothy-Douglas Alvey
2025-06-02 19:15:39 +0000 UTCbad thumbnail
L
2025-06-02 13:47:11 +0000 UTCNicely done, with a million views halfway through the day!
Terry Bollinger
2025-06-02 11:16:49 +0000 UTCGreat Video!! Can’t wait for the follow up.
Clark Ochikubo
2025-06-02 11:00:45 +0000 UTC
