2. INDEPENDENT STUDY PROJECT: ELECTROMAGNET JOAQUIN RIOJAS, PABLO RODRIGUEZ, DARIO LARRALDE MR. DAVIS PERIOD 3, SCIENCE JANUARY 28, 2014

3. ELECTROMAGNETISM By definition an electromagnet is a type of magnet in which the magnetic field is produced by an electric current. The magnetic field disappears when the current is turned off. When electricity passes through wires a magnetic field is created around the wire, when wound into a coil this field concentrates because the magnetic field of all the turns of wire passes through the center of the coil, creating a strong magnetic field there. In order to amplify the magnetic field a ferromagnetic material is placed inside the coil. For our experiment we used a Ferromagnetic core. The core is composed of small regions called magnetic domains, when a current if not present the domains point in random directions and cancel each other out. When the magnetic field from the wire coils passes through the core, the domains are aligned parallel to the magnetic field so their field add to the wire’s creating a large field.

4. CIRCUIT DIAGRAM Key Battery Electromagnet

5. VARIABLE I- COIL The first variable that affected the strength of our magnet we wanted to test was the tightness of the coil. We wanted to know that if the coil was tighter would the magnet be more powerful; the answer was simple, yes. By creating a tighter coil the magnetic field would be more concentrated and therefore more powerful. Using a tighter coil resulted in a more powerful magnet.

6. VARIABLE II-INSULATORS Initially, we built our magnet using a bare copper wire as the coil, this worked very well and gave us no trouble; however, we wanted a more powerful magnet. Thinking that the more tightly wound up the coil was the more electric field it was going to create and the more powerful the magnet, and knowing that the coil loops could not touch, we decided to use an insulated wire that allowed us to use more loops and created a more powerful field. However to properly use the insulated wire we needed a great deal of wire to make it a multiple layer coil, because the space the insulator took up made the loops further apart. So for a single layer coil, bare wire was used because it could have more frequent loops.

7. VARIABLE III- POWER SOURCE For our first magnet we used a 6V battery. For the second magnet a 9V, for the third two 6V. For the fourth magnet we used two 9V batteries, then we used two 6V and two 9V! However for our final magnet we combined the power of four 9V batteries to create a 36V power source for out electromagnet. Each time we used more power the magnet worked better, with this data we can conclude that the more current passing through a wire the greater its magnetic field is.