How an accelerometer works

An evening pause: A little dense for non-engineers, but just clear enough to be educational for all.

Hat tip Edward Thelen.

As always, I am in need of suggestions for evening pauses. If you’ve seen something you think will fit, place a comment here, in this post, but don’t post a link to your suggestions. I will contact you so that you can send it to me direct and I can then schedule it.

Nebraska rare earth mineral discovery to challenge China’s monopoly

A discovery in Nebraska of rare earth minerals appears set to challenge China’s monopoly.

To me these were the key quotes from this article:

The U.S. used to produce rare earths through the Mountain Pass Mine in California, but it was shut down in 2002, primarily because of environmental concerns, including the spillage of hundreds of thousands of gallons of water carrying radioactive waste into a nearby lake.

and

Although studies have shown the U.S. has 13 million metric tons of rare-earth minerals, National Mining Association spokeswoman Carol Raulston said it does not mine any of it – partly as a result of the difficulty of obtaining permits. “One of the key problems that investors tell us about is that the permitting regime in this country is so complicated and time-consuming that it has hurt investments here in the United States,” Ms. Raulston said.