Big G revisited

摘要

Measuring Newton's constant of gravitation is a difficult task, because gravity is the weakest of all the fundamental forces. An experiment involving two simple pendulums provides a seemingly accurate but surprising value.rnNewton's law of universal gravitation is a pillar of classical physics. Here's a quick textbook example: the gravitational force between any two spherical objects is proportional to the product of their masses and inversely proportional to the square of the distance between their centres.