What's The Difference Between Centrifugal And Centripetal Forces?

Centripetal and centrifugal forces are central to circular motion, but they're not the same. Discover the differences between ...
The New York Times

What ‘Security Guarantees,’ in the Form of Troops, Could Look Like in Ukraine

President Trump has not committed to adding American forces to the mix in Ukraine. No one has detailed publicly what form defenses would take, but there are several options. By David E. Sanger ...