Activity 1.docx 3t1el

Activity 1 How it came about... The Electromagnetic Wave Theory Contributions

Scientists

a.Contributed in developing equations that showed the relationship of electricity and magnetism

C 1. Ampere

b.Showed experimental evidence of electromagnetic waves and their link to light

D 2. Faraday B 3. Hertz

c.Demonstrated the magnetic effect based on the direction of current

A 4. Maxwell

d.Formulated the principle behind electromagnetic induction.

E 5. Oersted

E.Showed how a current carrying wire behaves like

II.CONCEPT WEB

Amper e Contributio ns Demonstrated the magnetic effect based on the direction of current. -He discovered the nature of the relationship between electric current-flow and magnetism, as well as the relationships of the behavior of electric currents in various types of conductors. -His theory is called

Farad ay Contributio ns -Formulated the principle behind electromagnet ic induction. -1821 Faraday built the first electric motor--a device for transforming an electrical current into rotary motion. 1331 Faraday made the first transformer. -The unit of capacitance is named after

Scienti sts Hertz

Contributio ns -Showed experimental evidence of electromagnet ic waves and their link to light. -Discovered the Hertzian waves which is known as the radio waves -Hertz is the unit used to measure the frequency of waves. -He was the first person to demonstrate

Maxwe ll Contributio ns - Contributed in developing equations that showed the relationship of electricity and magnetism -He wrote a mathematical treatise formalizing the theory of fields in 1856.In the year 1873 Maxwell published Electricity and Magnetism, demonstratin g four partial differential equations that completely described

Oerste d Contribution s - Showed how a current carrying wire behaves like a magnet. -Through research and experiment, Oersted established that an electric current running through a wire creates a circular magnetic field. His work led other scientists to develop mathematical formulas relating electricity to magnetism, and was a major step toward a

FARADAY1831: Discovery of Electromagnetic Induction

This was an enormously important discovery for the future of both science and technology. Faraday discovered that a varying magnetic field causes electricity to flow in an electric circuit.

electromagentic-induction-horseshoe Moving the magnet causes a current to flow. You need a sensitive ammeter to observe the tiny current caused by a small magnet. The stronger the magnet, the bigger the current. Pushing a bar magnet into a coil of wire can generate a larger current. For example, moving a horseshoe magnet over a wire produces an electric current, because the movement of the magnet causes a varying magnetic field. Previously, people had only been able to produce electric current with a battery. Now Faraday had shown that movement could be turned into electricity – or in more scientific language, kinetic energy could be converted to electrical energy.

Most of the power in our homes today is produced using this principle. Rotation (kinetic energy) is converted into electricity using electromagnetic induction. The rotation can be produced by high pressure steam from coal, gas, or nuclear energy turning turbines; or by hydroelectric plants; or by wind-turbines, for example.

OERSTED Discovery of Electromagnetism Oersted’s famous experiment, showing that electricity and magnetism are linked, took place during a lecture on April 21, 1820, when Oersted was 42 years old. In this experiment he ed electric current through a wire, which caused a nearby magnetic com needle to move. Oersted's experiment

Oersted notes Oersted’s original notes. He shows how an electric current flowing in a wire causes a nearby magnetized com needle to turn. Over the next few months Oersted carried out more experiments, discovering that electric current produces a circular magnetic effect around it. circular magnetic field

Oersted showed that electric current produces a circular magnetic effect around it. Oersted announced his discovery on July 21, 1820, in a paper consisting of four pages of Latin, which was soon translated into most of the main European languages. In English Oersted’s paper had the title Experiments on the Effect of a Current of Electricity on the Magnetic Needle. By September 1820 François Arago was demonstrating the electromagnetic effect to ’s scientific elite at the French Academy, which almost immediately led AndréMarie Ampère to take the next great steps in the story of electromagnetism. Just as Volta’s invention of the battery had opened new horizons in physics and chemistry, Oersted’s discovery of a link between electricity and magnetism unleashed a revolution in physics leading us into our current digital world.