Spill-Proof Cups Aren’t Magic—They’re Physics! by Rhett Allain from on 2017-02-01 18:33 (#2B40D) There is a popular mug that doesn't spill. Here's how it might work, along with an estimate of the maximum tipping force to knock it over. The post Spill-Proof Cups Aren't Magic-They're Physics! appeared first on WIRED.