His first experiments involved driving a simple pendulum with a pulse motor. He discovered that the easiest way to keep the pendulum moving was to use a coil to detect when the it reached the ...

This case is fairly simple, because here the earth and the pendulum are not exerting much influence on each other. As you move off the north pole down to a more southerly point like Washington, for ...

All you need to make it happen is a hula hoop (and some patience!). View the original article to see embedded media. "HIS ...