Changes between Version 27 and Version 28 of ElectricalIntroduction

Timestamp:

Aug 28, 2017, 8:46:56 PM (8 years ago)

Author:

David Albert

Comment:

--

ElectricalIntroduction

@@ -149 +149 @@
 == Electromagnets ==
 [[Image(http://cdn.hitfix.com/photos/4366059/Magneto-floats-on.jpg,20%,right,nolink)]]
-When electricity moves through a conductor, it [https://www.khanacademy.org/test-prep/mcat/physical-processes/magnetism-mcat/a/using-the-right-hand-rule generates a magnetic field] around the conductor.  If you shape the conductor into a coil (like a spring), the field is concentrated and becomes stronger. The more current, the stronger the magnetic field.  Industrial electromagnets can lift 25-30,000lbs (think truck); electromagnets hold the door shut at the bank.  2537 has used electromagnets to hold and release heavy mechanisms.
+When electricity moves through a conductor, it [https://www.khanacademy.org/test-prep/mcat/physical-processes/magnetism-mcat/a/using-the-right-hand-rule generates a magnetic field] around the conductor.  If you shape the conductor into a coil (like a spring), the field is concentrated and becomes stronger. The more current, the stronger the magnetic field.  Industrial electromagnets can lift 25-30,000lbs (think truck); electromagnets hold the door shut at the bank.  2537 has used electromagnets to hold and release heavy mechanisms.  Electromagnets often use ferromagnetic materials (like iron cores) to concentrate the magnetic flux.
 
 * Exercise:
@@ -156 +156 @@
       * Connect the electromagnet to the battery terminals
       * Pick stuff up with the magnet
- 
+
+* Bonus Exercise: Make an [http://www.electronics-tutorials.ws/electromagnetism/electromagnets.html electromagnet]
+  * Materials: battery, insulated wire, large nail, paperclips or small nails
+  * Activity:  (see [https://www.youtube.com/watch?v=_odHVX4mUAQ here])
+       * Strip the end of the wire and, leaving ~4" free, wrap the rest of the wire around the nail in a tight coil.
+       * Strip the other end of the wire and leave ~4" free
+       * Connect the two ends of the coil of wire to a battery and see how many nails/paperclips your electromagnet can hold
+  * What happened: When you passed an electric current through your coil, it generated a magnetic field that was concentrated by the nail. 
 
 == DC Motors ==