Teacher: "Why are you late this morning?"
Student: "Its my alarm clock. Everyone got up except me!"
Teacher: How did the alarm clock make you the only one not to get up?"
Student: "There are eight of us in the my family and the alarm clock was only set for seven."
Galileo FerrarisBorn 31 Oct 1847; died 7 Feb 1897 at age 49.Italian physicist who studied optics, acoustics and several fields of electrotechnics, but his most important discovery was the rotating magnetic field. He produced the field with two electromagnets in perpendicular planes, and each supplied with a current that was 90º out of phase. This could induce a current in a incorporated copper rotor, producing a motor powered by alternating current. He produced his first induction motor (with 4 poles) in May-Jun 1885. Its principles are now applied in the majority of today's a.c. motors, yet he refused to patent his invention, and preferred to place it at the service of everyone.« |
