When buying a pair of shoes, you might not necessarily do so directly from the brand. You’ll probably head over to theRoadrunnersportsorZapposwebsite, or perhaps your localFootlocker,Dickssportinggoodsor family owned running store. These stores and chains buy it from brands such as adidas and...
Gravity does not, in general, point toward the center of mass. Take for example the Earth-Moon system. Despite its non-contiguous-ness, it’s still a perfectly legit collection of mass. The center of mass of the Earth and Moon combined is a point just a ...