Voltage Current and Power

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Voltage Current and Power
Static Electricity electrical energy at rest.
Dynamic Electricity Transfer of energy from a
source to a Load.
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Alessandro Volta
1799 he had developed the so-called voltaic pile,
a forerunner of the electric battery, which
produced a steady stream of electricity. In honor
of his work in the field of electricity. The
electrical unit known as the volt was named in
his honor.
Volt Measurement of Electromotive Force
(EMF) The Letter Symbol for Volt is E Example
Voltages Dry Cell 1.5v Car Battery
12v House Outlet 120V
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Andre Ampere
He developed a quantitative relationship for the
strength of a magnetic field in relation to an
electric current (Ampere's theorem) and
propounded a theory as to how iron becomes
magnetized.  Ampere also devised a rule governing
the mutual interaction of current-carrying wires
(Ampere's law) and produced a definition of the
unit of measurement of current flow, now known as
the ampere. The ampere is the unit for measuring
electric current.
Ampere (amp) measure of the volume of electrons
moving through a circuit. 1A
6,280,000,000,000,000,000 electrons per sec Or
6.28 x 1018 electrons/sec The letter symbol
for Amp I
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Requirements Must have sufficient amount of
both voltage and current to activate a
load. Flash light battery vs. Car Battery
Could you start a car with Flash light batteries?
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Small and Large Voltage Amounts
Giga (G) 1,000,000,000 Thousand Million Mega
(M) 1,000,000 Million Kilo (K) 1,000
Thousand Milli (m) .001 Thousandths
(1/1000) Micro (m) .000 001 Millionths Nano
(h) .000 000 001 Billionths Pico (r) .000 000
000 001 Trillionths
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Direct Current D.C.
9v
Voltage always has the same fixed polarity.
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Alternating Current A.C.
Has changing polarity ( -) Produced by
generators (power plant) or alternators (car)
Frequency - cycles / sec 1Hz
Cycle
House current 60 Hz Radio Am KHz Fm
MHz Radar GHz
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AC Used for Power Transmission - Motors -
(induction) Electro Magnetism ? Solenoid
pulling magnet
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AC is made when a magnetic field passes by a
conductor (wire). This produces a current in the
wire. A coil is usually used to intensify the
effect.
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Direct Current used in most electronic
equipment How Made
D.C. Generators chemical cell
(batteries)- Contain electrolytes Chemical
solutions that contain ions.
Cells have a positive plate (Anode ) and a
negative Plate (Cathode -)
Electrons flow from Cathode (-) to Anode
which makes current
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A cell that uses a liquid solution is a WET Cell
A Cell where the electrolyte is absorbed into
paper or changed into a paste is called a dry
cell.
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D.C. Thermo Electric Generator- If a junction of
two dissimilar metals is heated, a small DC
current will be produced.
A Thermocouple works on this idea.
(furnace/oven) control.
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How Direct current is made from alternating
current.
Conversion from A.C. to D.C. ---gt uses Diodes
1 Diode Half-wave rectifier
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4 Diode- Full wave Rectifier uses 4 diode
network rectifies both halves of A.C. Signal.
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Using capacitors in a rectified signal tends to
smooth out the ac bumps.