How gravity causes a perfectly spherical ball to roll down an inclined plane is part of elementary school physics canon. But the world is messier than a textbook. Scientists in the Harvard John A.

Prefer Newsweek on Google to see more of our trusted coverage when you search. A number of mysterious large spherical objects have washed up on the beaches of the Black Sea between March and July, ...

How gravity causes a perfectly spherical ball to roll down an inclined plane is part of the elementary school physics canon. But the world is messier than a textbook. Scientists in the Harvard John A.