12.3: Electric Charge

Greek

they noticed that rubbed amber attract pieces of dry leaves and feathers

Rubbed amber

Greek noticed that ________________ attracts pieces of dry leaves and feathers

Dry leaves and amber

according to the Greeks, rubbed amber attracts pieces of

Elektron

amber means

600 BC

when did greeks discover that rubbed amber has an electric charge

There were more substances that exhibit the behavior of attracting dry leaves

what happened in 16th century

glass rod, comb, and sulfur

in 16th century, what were the substances/objects that exhibit attraction towards dry leaves

1600, William Gilbert

in _________, the phenomenon was explained by ______________________ in his book De Magnete

De Magnete

what is the book created by William Gilbert

electricus

what was the new latin word used by William Gilbert in his book

of amber

electricus means

Neils Bohr

in 1913, he is the danish scientist who created the planetary structure of an atom

Planetary structure of atom, 1913

what did neils bohr create and when

Proton

Electron

Neutron

what are the 3 subatomic particles

Proton

it is the positively charged subatomic particle

Electron

negatively charged subatomic particle

neutron

neutral charged subatomic particle

1.6 x 10^-27 kG

mass of proton

1.26 x 10^-27 kG

mass of neutron

9.1x10^-31 kG

mass of electron

number of protons

____________________ give the identity of the atom

T

T or F. Number of proton and electrons are the same in a neutral atom

neutral electrical condition

when an atom has an equal number of protons and electrons, the atom is said to be at its

0

net electrical charge of a neutral atom

mass number - number of protons/electrons

how is the number of neutrons calculated

valence electron

refers to the electrons on the outermost shell

a. when an atom loses electron

b. when an atom gains electron

how does an atom become

a. positively charged atom

b. negatively charged atom

electron

it is the subatomic particles that is being transferred

18th Century, Benjamin Franklin

in _______________, it was discovered by ________________ that electric charges can either be positive or negative

electric charges can either be positive or negative

what did Benjamin Franklin discover

- electric charges can either be positive or negative

- most substances are penetrated by what he called electric fire/fluid

- the term "electric fire" was coined

- when an object has too much of this fire, it becomes positively charge

- when an object has a deficiency of this fire, it becomes negatively charge

benjamin franklin electric charge story

18th century

when was the term "electric fire" coined

1. when you create positively charged object by putting electric fire, you are automatically creating a negatively charged object (Law of conservation of charge)

2. if you add more electric fire on the object, the object becomes more positively charged and automatically creating a negatively charged object, the attraction increases

3. when you bring these two object closer, the attraction increases

observations of benjamin franklin

Joseph John Thomson

who discovered the electron

Ernest Rutherford

who discovered the proton

James Chadwick

who discovered the neutron

+e = 1.602 x 10 ^-19 coulomb

charge of a proton

-e= 1.602 x 10 ^ -19 coulomb

charge of an electron

Electric charge

basic property of matter carried by some elementary particles

Coulomb

SI unit of electric charge

Charles Andre de Coulomb

Coulomb came from

6.28 x 10^18 electrons

1 coulomb is equals to _______________ electrons

attract

opposite charges

repel

same charges

Attract

negative + positive

repel

negative + negative

- charges can neither be created nor destroyed

- charges can only be transferred one body to another

law of conservation of charges

Conductors

- materials that permit electrons to flow freely from particle to particle

- are metals

- electrons of these are not tightly bounded to their atom

Metal

material that has the tendency to give its electrons easily

Silver

what is the best metal for conducting electricity

NOT

electrons of metals are ________ tightly bounded to their atoms

silver, gold, copper, steel, sea water

5 conductors of electricity

insulators

- materials that dont permit electrons to flow freely from one particle to another

- are nonmetals whose electrons are tightly bounded to their atoms causing to not lose electrons but only gain

rubber, glass, oil, diamond, dry wood

5 electrical insulators

- two objects should be physically contact

- before contact: two objects are uncharged (neutral)

- after contact: two objects become oppositely charged

charging by friction

- no physical contact

- before contact: one object is charged (+ or -)

- after contact: the other acquire opposite charge

charge by induction

- physical contact

- before contact: one object is charged (+ or -)

- after contact: the other object acquired the same charge

charging by conduction

charging by friction

charging by induction

charging by conducting

3 methods of charging