![Dan Kurtz on Twitter: "Here's what the 2019 official KBO baseball looks like. What's different? A lower coefficient of restitution to match NPB's COR specs (0.4034-0.4234), larger circumference (from 234mm to 235mm), Dan Kurtz on Twitter: "Here's what the 2019 official KBO baseball looks like. What's different? A lower coefficient of restitution to match NPB's COR specs (0.4034-0.4234), larger circumference (from 234mm to 235mm),](https://pbs.twimg.com/media/DyVjmeVUcAAb5Ig.jpg)
Dan Kurtz on Twitter: "Here's what the 2019 official KBO baseball looks like. What's different? A lower coefficient of restitution to match NPB's COR specs (0.4034-0.4234), larger circumference (from 234mm to 235mm),
![Forces on a spinning baseball in flight. The drag force F D acts in the... | Download Scientific Diagram Forces on a spinning baseball in flight. The drag force F D acts in the... | Download Scientific Diagram](https://www.researchgate.net/profile/Alan-Nathan/publication/259103270/figure/fig1/AS:689597356974080@1541424230079/Forces-on-a-spinning-baseball-in-flight-The-drag-force-F-D-acts-in-the-v-direction-the_Q320.jpg)
Forces on a spinning baseball in flight. The drag force F D acts in the... | Download Scientific Diagram
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