Slide 1

Electrostatic

PRESENTED BY :

SUJARWANTO

4001410066

Electrostatic charge

Static electricity is studying electrical charges at rest.There are 2 types of electric charge:

Positive charge (protons). Proton is an elementary particle carrying a positive charge.

Negative charge (electrons). Electrons are elementary particles carrying negative charge.

Positively charged object, when the number of electrons in the atom are smaller than the number of protons.

Negatively charged object, when the number of electrons in the atom are greater than the number of protons.

Neutral objects, when the number of electrons in the atom are equals the number of protons.

Atom Theory

Atom is neutral because many protons in the nucleus of an atom are same with many electrons surrounding the nucleus. Electrons can exit or enter into the arrangement of atoms, especially the outermost electrons (valence electrons). If the electrons out of the arrangement of atoms, the number of protons more than the number of electrons, so that the atoms charged positively.

Coulombs Law

The Law of Coloumb:"Attractive force or repulsive force between two electric charges is proporsional to the charges and inversely proportional to the square of separation distance

Mathematically:

With:

Fc = coulomb force (N)

r =distance between 2 cargo

k =comparison factor (k = 9x109 Nm2C-2)

qa= first cargo

qb =second cargo

Electrostatic Interaction between Two Electric charge

Between two electrically charged objects brought near each other, electrostatic interactions will arise, that are :Pull, if the two objects different types of cargo.Reject, if the two objects toward each other similar charge.

The Electric Field

The electric field is the space around the electrically charged objects where other electrically charged objects are placed in this space have electric style.

Strong electric field is a quantity that is used to express the vector electric field around an electric charge can be described by the line - an imaginary line called the line - the line style. Lines of force outward cargo remain positive and go into the charge to the charge remains negative.

Strength Electric Field

Strength electric field (given the notation E) is stated the amount of coulomb force per unit charge.

Mathematically :

with:

F =electric force experienced to the charge q1 because q2

E = strength electric field (N/C)

q =load testers(C)

Magnitude of strength electric field and the constant charge q1.

In general, strength electric field formula at a point to a certain distance from the constant charge q is:

With :

r = the distance between a point to the constant charge (m)

q = constant charge (C)

E = strength electric field (N/C)

Electrostatic Potential

Electric charge that placed in the positive electric area will through a coulomb force (F). If the charge q under the influence of the force,it will moved from point A to point B, the work that must be doing, Wa-b, on the charge to pass through the small track from point 1, 2, 3, ... ....

&

with :

Ep = potential energy load tester q (J)

k = 9x109 Nm2C-2

q = load testers(C)

q= load resource (C)

r = the distance between load testers to load resource (m)

The potential energy in anywhere

With:

Ep= electric potential energy for q

Electric flux

Electric flux is the number lines of force that penetrates perpendicular to the field.

Mathematically:

with :

= electric flux (N/C m)

E = strength electric field (N/C)

A = Surface area (m2)

= the angle between strength electric field with the field

1 N/C m = 1 weber

The Law of Gauss

The law of Gauss is based on the concept of force lines (force field) that penetrate a surface.The number of force lines that penetrates a surface vertically at each point is proportional to the strength electric field at that point and it expressed by the equation:

E = strength field that perpendicular to the field

o = permetivitas vacuum

An = surface area that penetrated the line style

N = the number of lines of force The sound of Gauss' law: "The number of force lines that penetrates a surface is proportional with the amount of electric charge that covered by the closed surface"

N= q

Electrostatic Potential

Potential difference between points A and B (VB-VA) is defined as the effort per unit of cargo.

With:

q=charge transferred (C)

V= potential difference (V)

W= attempt to move the cargo (J)

or

Strength Electric Field on 2 Parallel Plate

Meeting of the charge () is the charge per unit area of chip.

The number of force lines that permeates chip is

Because the electric field penetrates perpendicularly into pieces, then cos = 1, so

Electric Capacity

Capacitor

Formation of two conductor which its shape is no particular and neutral attributed to a battery, till arise potential difference V among both and each charge conductor +q and q.

Capacitor capacity

Capacities a conductor is comparison between payload conductor and its potential.

With:

C = capacitor capacity (farad)

Q= capacitor charge (Coloumb)

V= potential difference at the end of capacitor (V)

Parallel Chip Capacity

With :A = large of pieces (m2)d = distance between 2 pieces (m)C = capacitor capacity(farad)o = Permittivity of vacuum

If inserted the insulator with permittivity o with = o. r, so

Capacitor Structure

Composition of Parallel CapacitorsIn this arrangement applies:1. Potential difference of each capacitor is equal and also equal to the voltage sourceV1 = V2 = V2. The load capacitor replacement equal to the amount of cargo in each capacitor.q = q1 + q2

The charge of each capacitor

q1=C1.V and q2=C2.V

The load capacitor replacement

q=Cp.V

So

Cp.V=C1.V+C2.V

Cp = C1 + C2

Composition of Series Capacitors

In the arrangement of series capacitor applies:1. The load on each capacitor is the same, which is equal to the charge on the capacitor replacement.q = q1 = q22. Potential difference at the end of the capacitor replacement equal to the number of potential differences at the end of each capacitorV = V1 + V2

With

With subtitution V, obtained

Capacitor replacement series comprising n capacitors

Stored Energy in Capacitor

The average of Potential difference during the process of moving cargo

Effort required

Because

or

With

W= capacitor Energy (J)

C= capacitor capacity (F)

V=Potential difference (V)

q= load capacitor (C)

Question

1. A circle conductor have charge +106 C, diameter 16 cm. Calculate the potential on the distance 10 cm, 8 cm, and 6 cm from the centre conductor!

2. Berapakah gaya listrik yang bekerja pada eletron hidrogen oleh proton (inti atom hidrogen) bila eletron mengelilingi proton pada jarak rata rata 0, 53x10-10 ?

(qe=-1,6x10-19 C)