```                                          ELECTRICITY
Electricity                                             Negative charge (-)
    It is the set of physical phenomena                   It has more electrons than protons
associated with the presence and flow of               (Ne>Np).
electric charge.                                      Negative charge attracts other positive
    It is a form of energy. Also, it is the flow           charges and repels other negative charges.
of electrons.                                         The negative charge is attracted by other
    It gives a wide variety of well-known                  positive charges and repelled by other
effects, such as lightning, static electricity,        negative charges.
electromagnetic induction and electric
current.                                                        Charge of elementary particles
Particle        Charge (C)       Charge (e)
Electron        1.602×10-19 C          -e
Electric Charge (Q)
Proton          1.602×10-19 C         +e
Neutron              0C                0
    It is a property of some subatomic
particles,    which      determines       their
electromagnetic interactions.                      Coulomb"s Law
    Electric charge generates electric field.
   It describes force interacting between
The electric charge influence other electric
static electrically charged particles.
charges with electric force and influenced
   It states that the force between two
by the other charges with the same force in
charges is proportional to the amount of
the opposite direction.
charge on both charges and inversely
    The SI unit of electric charge is the
proportional to the square of the distance
coulomb (C). One coulomb has the charge
between them.
of 6.242×1018 electrons: 1C = 6.242×1018
e                                                          k . q1 . q2
F
r2
Q=I·t
Where, F = Force
Q is the electric charge, measured in coulombs              k = a constant, 8.988×109 N·m2/C2
[C].
q1 = charge one
I is the current, measured in amperes [A].                  q2 = charge two
t is the time period, measured in seconds [s].              r = distance between the two charges
There are 2 types of electric charge:                   Electric Current (I)
   An electric current is a flow of electric
Positive charge (+)
charge.
    It has more protons than electrons                    In electric circuits this charge is often
(Np>Ne).                                               carried by moving electrons in a wire.
    The positive charge attracts other negative           It can also be carried by ions in an
charges and repels other positive charges.             electrolyte, or by both ions and electrons
    The positive charge is attracted by other              such as in a plasma.
negative charges and repelled by other                It measured in amperes.
positive charges.
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