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electric charge

positive charge:
- protons (atomic nucleus)
- (kat-) ions (ionized metal, ionized hydrogen, ionized gases... )

negative charge:
- electrons (atomic envelope)
- (an-) ions (remaining acid ions, ...)

force of repulsion between like charges
force of attraction between different charges

elementary charge, charge of an electron

force
directed quantity = vector
(draw an arrow with point of force + value + direction)

symbol:

Newton's law:
Hooke's law:    (linear-elastic materials)

gravity:


electrostatics:

energy

- a scalar physical quantity
- the ability to perform work, to take off heat or to emit light

symbol: E
unit: 1 Joule
symbol:


other units that also used:
electron volt: 1 eV = 1,602 * J
kilowatt hour: 1 kWh = 3,6 MJ
calorie :
1 cal = 4,2 J (small or gram calorie)
1 kcal = 1 Cal = 4,2 kJ (large / kilogram or food calorie)

Electricity

Electric charge: a property of some subatomic particles, which determines their electromagnetic interactions. Electrically charged matter is influenced by, and produces, electromagnetic fields.
Electric current: a movement or flow of electrically charged particles, typically measured in amperes.
Electric field: an influence produced by an electric charge on other charges in its vicinity.
Electric potential: the capacity of an electric field to do work on an electric charge, typically measured in volts.
Electromagnetism: a fundamental interaction between the magnetic field and the presence and motion of an electric charge.

speed of light
light speed

symbol: c
Value in vacuum:
c = 299,792,458 metres per second = 1 Planck unit
(Sunlight takes about 8 minutes, 19 seconds to reach Earth, but, due to refraction, scattering, gravity and so on, about 100000 years to reach the surface of the sun from it's core)

- the maximum speed in the universe
- a constant of nature
- in a medium reduces the speed of light
- different types of light wave will travel at different speeds.

Approximate values:
300,000 kilometres per second        
1,079 million kilometres per hour        
186,000 miles per second                
671 million miles per hour                
173 astronomical units per day

real animation: Speed_of_light_from_Earth_to_Moon

galvanic separation



example: Pyro- und Piezoeffekt bei Turmalinkristallen

voltage source

DC:
cell
battery (3 or more cells in series connection)
accumulator = rechargeable battery or storage battery

AC:
alternating current generator (AC generator)
power supply unit
power transformer
power adaptor

series circuit
series connection


I = constant
U = U1 + U2 + ...
R = R1 + R2 + ...

shunt circuit
parallel circuit
parallel connection

U = constant

I = I1 + I2 + ...

rectification

converter of AC to DC

current
(strength of electric current)

Def.: physival value - means the rate of flow of electric charge through the surface of the conductor (a quantity)
symbol: I
unit: ampère (the rate of one coulomb per second)
symbol: 1 A

voltage
(electrical potential)

Def: physical value (quantity) for galvanic separation
symbol: U
unit: volt
symbol: 1V


(see also: galvanic separation)

resistor (device)
resistance (value)
reluctance (magnetical resistance)
inductance (resistance of an inductor in alternating current = AC)

Def.: physical value, how strong the electric current is restricted
symbol: R
unit:      1 (Ohm)
symbol and basic units:
             
formula:
             

resistivity
(specific electrical resistance or volume resistivity)

Def: measure of how strongly a material opposes the flow of electric current
symbol: ("Rho")

unit:
         
      
or