the unification of electricity, magnetism and light

7/29/2019 The Unification of Electricity, Magnetism and Light

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Our lives have been filled with mysteries about theunexplained events that happened in theenvironment. Questions like Why does thishappen?", "How does it happen and other

questions that will certainly left your mindwondering. Our scientists have observed thesenatural phenomena and explained these events toenlighten the society and to be aware of oursurroundings. Phenomena such as the electrical

phenomena, magnetic phenomena, andelectromagnetic phenomena which have greatlyaffected our lives.


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Electrical Phenomena: Coulombs Law

Magnetic Phenomena: Experiment of Oerstedand Ampere

Electromagnetic Phenomena: Faradays Law ofInduction


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-Electric Charge

-Charge Distribution

-Charge Conservation

-Charge Quantization

-Coulomb Force-Coulombs Law

-Electric Field

-Electric Lines of Force

Basic Pr incip les Governing Electrostat ics


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Basically define simple terms such ascharge, electron, proton etc.

Differentiating a positive charge from anegative charge and Laws

Know common errors in viewing thehistory of electricity.

Understand the distribution of electricity.

State basic laws of the electric phenomena.

Give recognition to the scientists whocontributed to the development ofelectricity.

Have the ability to relate it with life


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2 Kinds of Electric Charge

1) Positive- the kind carried by proton.

2) Negative- the kind carried by negative.

Elementary Charge

qe= 1.60 10-19 C

Magnitude CoulombCharge


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American Inventor

Statesman and scientist

Popular in the Kite Flying Experiment Introduced the terms positive charge and

negative charge

Believed that electric charge is a fluid going in

and coming out. Rubbing two different kinds of substances

together may cause the transfer of electronsfrom one material to the other.

Birth: January 17, 1706Death: August 23, 1806


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Despite what you have learned, BenjaminFranklin did not invent electricity. In fact,electricity did not begin when BenjaminFranklin at when he flew his kite during athunderstorm. The first discoveries ofelectricity were made back in ancientGreece. Greek philosophers discoveredthat when amber is rubbed against cloth,lightweight objects will stick to it. This is thebasis of static electricity.


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Triboelectric Series

- Is a series of substances arranged in orderbased from the electron affinity of thesubstance.

1) Copper with Silk

2) Glass with Silk

TRIBO ELECTRIC SERIES Celluloid Sulfur Rubber Copper,Brass Amber Wood Cotton Skin Silk Fur Glass Rabbit Fur Asbestos


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Methods of Charging

Charging by Friction

Charging by Conduction

Charging by InductionGrounding

Law of Electrostatic- Unlike charges attract, Like charges repel


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Law of Conservation of Charge

Charge is neither created nor destroyed.Electric charge is merely transferred from

one place to another or from one system toanother.


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Law of Quantization of Charge

- Electric charge can only exist as integralmultiples charge in nature, the charge of

an electron.

q=+/- nqe

q= electric charge in Cn= number of electrons(+/-)qe= 1.60 x 10^-19 C


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Measured in the experimentsperformed by Robert Millikan and otherscientists.

The unit of charge is Coulomb in honorof Charles Agustin de Coulomb.

1.60 x 10^-19 C


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An experiment performed by RobertMillikan and Harvey Fletcher in 1909.

Its objective is to measure the elementary charge of anelectron

The experiment entailed balancing the downward

gravitational force with the upward buoyant andelectric forces on tiny charged droplets of oil suspendedbetween two metal electrodes. Since the density of theoil was known, the droplets' masses, and therefore theirgravitational and buoyant forces, could be determinedfrom their observed radii. Using a known electric field,Millikan and Fletcher could determine the charge on oil

droplets in mechanical equilibrium. By repeating theexperiment for many droplets, they confirmed that thecharges were all multiples of some fundamental value,and calculated it to be 1.59241019 C, within one percentof the currently accepted value of 1.6021764871019 C. Theyproposed that this was the charge of a single electron.


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A French physicist. He was best known for

developing Coulomb's law, the definition ofthe electrostatic force of attraction andrepulsion. The SI unit of electric charge, thecoulomb, was named after him.

Lived in France

Born: June 14, 1736Died: August 23, 1806


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6.2415 1018 electrons = 1 Coulomb

One coulomb is the amount of charge inan electric current of one Ampere/second--

the Ampere being the current required toobtain an amount of magnetic forcebetween a pair of current carrying wires.The Millikan oil drop experiment, which

measures the charge on a single electron,provides the answer to how manyelectrons per second are in one Ampere.


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One of the strongest fundamental forces innature second only to electromagneticforce.

Electric force- a manifestation of this forcewhich involves the interaction of electriccharges that are stationary.

2 Kinds of Electric Force1) Attractive Force- -Fe, opposite charges.

2) Repulsive Forces- +Fe, like charges.


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q1 -q2

q2 on q1 q1 on q2

F1 F2


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Also known as Coulombs inverse squarelaw.

a law of physics describing theelectrostatic interaction

between electrically charged particles. first published in 1785

the magnitude of the Electrostatics force ofinteraction between two point charges is

directly proportional to the scalarmultiplication of the magnitudes of chargesand inversely proportional to the square ofthe distances between them.


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2 Conditions for Validity

The charges considered must be pointcharges.

They should be stationary with respectto each other.


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Fe = k q1 q2

d2

q1 and q2= magnitudes of 2 pointchargesFe= electrical forced= distance separating the chargesK= 9.0 x 109Nm2/C2


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Electrical Force GravitationalForce

Fe = k q1 q2d2

k = 9.0 x 109

Nm2

/C2

Fe = G m1 m2d2

G = 6.67 x 10-11Nm2/kg2

Fe > Fg by 1039


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Electric Field

acts when bothare charged.

Depends on thisformula.

Has a propertythat any charge

will experiencewhen placed atthis field

Gravitational Field

Acts between 2masses

Depends on theUniversal Law ofGravitation

Has a g= 9.8 m/s2


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E= F/q E= k Qq

d2

Electric Field Intensity- the force experiencedat a certain point by a test charge whenplaced in a region.

E= electric field

F= forceQ= unit chargeN/C= Unit of Electric Field

E= electric fieldK= Coulombs Constant

Q= source chargeq= test charged= distancesN/C= Unit of Electric Field


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Positive Negative

+ +


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Q1 Q2q

Fe 1 Fe 2


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Charge

there are two kinds of charge, positive andnegative

like charges repel, unlike charges attract

positive charge comes from having moreprotons than electrons; negative chargecomes from having more electrons thanprotons

charge is quantized, meaning that chargecomes in integer multiples of theelementary charge e

charge is conserved


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Studying the Electric Phenomena is very significant inour lives especially when we deal with natural eventsthat basically happen in the environment. It is trulyhelpful to us when we understand the basic principles ofthe electric phenomena because it helps us develop aclearer view of the subatomic world in the field of

electrons and protons which are subatomic particles. It issomehow coincidental to say that some formulas orlaws are similar in terms of the format and the onlydifference is the variable representation. Once weunderstand the electric phenomena on a subatomiclevel, we can explore a new level of knowledge andtechnology like how we develop machineries that run inelectricity. When we study these principles, we giverecognition to the great works of the different scientistswho worked hard to prove something or maybe spenttheir whole life deciphering these unexplained events.


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is a proportionality factor also calledthe electric force constantor electrostatic constant.

The exact value of Coulomb's constant is:

the unification of electricity, magnetism and light

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