History of Electromagnets

       The first recorded discovery of the relation between electricity and magnetism occurred in 1820, when Danish scientist Hans Christian Oersted noticed that the needle on his compass pointed away from magnetic north when a nearby battery was turned on. This deflection convinced him that magnetic fields radiate from all sides of a wire carrying an electric current, just as light and heat do.

   Shortly thereafter, he published his findings, showing mathematically that an electric current produces a magnetic field as it flows through a wire. Four years later, English scientist William Sturgeon developed the first electromagnet, which consisted of a horseshoe-shaped piece of iron wrapped with copper wire. When current passed through the wire, it would attract other pieces of iron, and when the current was stopped, it lost magnetization.

       Though weak by modern standards, Sturgeon’s electromagnet demonstrates their potential usefulness. Despite only weighing 200 grams (7 ounces), it could lift objects that weighed approximately 4 kg (9 pounds) with only the current of a single-cell battery. As a result, research began to intensify into both electromagnets and the nature of electrodynamics.

         By the 1930’s, American scientist Joseph Henry made a series of improvements on the design of the electromagnet. By using insulated wire, he was able to place thousands of turns of wire on a single core. As a result, one of his electromagnets could support as much as 936 kg (2,063 lbs) of weight. This was to have a popularizing effect on the use of electromagnets.

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                                              5W+1H 

1. What is considered by Oersted? 
    * Oersted pointed away from magnetic north when a nearby 
       battery was turned on.

2. Who was first to develope electromagnet?
    * William Sturgeon

3. When was Electromagnet found?
    * In 1820

4. Where is Oersted from?
    * He is come from Danish(Denmark) 

5. Why can horseshoe be wrap around the electric current carrying       wires to attract iron? 

    * Because the electric current passing through a wire generates a
       magnetic field

6. How did Joseph Henry made a series of improvements on
    the design of the electromagnet?
    * By using insulated wire

Active and Passive

1) *Active   :  American scientist Joseph Henry made a series

                       of improvements on the design of the electromagnet                          by the 1930’s.

    *Passive  :  A series of improvements on the design of the                                    electromagnet was made by scientist Joseph Henry,                          the 1930’s.

2) *Active   :  Four years later, English scientist William Sturgeon                          developed the first electromagnet, which consisted of                        a horseshoe-shaped piece of iron wrapped with                                  copper wire.

     *Passive : The first electromagnet, which consisted of a                                      horseshoe-shaped piece of iron wrapped with copper                        wire was developed by English scientist 

                       William Sturgeon four years later.

3) *Active   : This deflection convinced him that magnetic fields                            radiate from all

                       sides of a wire carrying an electric current.

    *Passive  :  He was convinced that magnetic fields radiate from                          all sides of a wire carrying an electric current by this                        deflection.

4) *Active   :  Danish scientist Hans Christian Oersted noticed that                          the needle on his compass pointed away from                                    magnetic north when a nearby battery was turned on.

    *Passive  :  The needle on Danish scientist Hans Christian                                  Oersted compass pointed away from magnetic north                          was noticed by him, when a nearby battery was                                turned on.

Nominal and Verbal Sentenses

Nominal Sentences

1.This was a popularizing effect on the use of electromagnets.
   Tenses: Past Tense

2.There were thousands of turns of wire on a single core.
   Tenses: Past Tense

Verbal Sentenses

1. American scientist Joseph Henry

                        S

     made  a series of improvements on the design of

         V                                           O

     the electromagnet, by the 1930’s.

     Tenses    : Past Tense

     Because : This sentences explains about    

                      improvement on the design of the    

                      electromagnet.

2. Four years later, English scientist William Sturgeon

                                                         S

    developed the first electromagnet, which consisted of

           V                         O

    a horseshoe-shaped piece of iron wrapped with copper  wire.

    Tenses   : Past Tense

    Because :This sentence explained the early development   

                     of the electromagnet.

3. This deflection convinced him that magnetic fields radiate

              S                    V         O

    from all sides of a wire carrying an electric current.

    Tenses: Past Tense

Conclusion

        The first recorded discovery of the relation between electricity and magnetism occurred in 1820, when Danish scientist Hans Christian Oersted noticed that the needle on his compass pointed away from magnetic north when a nearby battery was turned on. Four years later, English scientist William Sturgeon developed the first electromagnet, which consisted of a horseshoe-shaped piece of iron wrapped with copper wire. By the 1930’s, American scientist Joseph Henry made a series of improvements on the design of the electromagnet. By using insulated wire, he was able to place thousands of turns of wire on a single core.