The first condition is very important. The small electromagnets which are commonly used by oculists often fail at the critical moment, owing to their lack of adequate magnetic strength ...

In use, the electromagnet is powered up by a small 12-volt power supply, fixing the jig in place on the stock. The angle grinder is traced around and makes a surprisingly clean cut. Check out the ...

They are found in electric motors and loudspeakers. Electric bells like the ones used in most schools also contain an electromagnet. The slideshow describes how an electric bell works.

The phone uses an app that talks to the Arduino ... Instead of a hot end pointing down, the mechanism has an electromagnet pointing up. A small washer in the base of each chess piece makes it ...