The document is a presentation about electrical circuits and alternating current. It contains definitions of terms like nodes, steps for determining voltage in a circuit, Norton's theorem for replacing a two-terminal circuit with an equivalent circuit, equations for alternating current, and advantages of AC over DC current. The presentation was given by four students from the Computer Science and Engineering department at Dhaka International University to their lecturer.

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WELCOMEWELCOME
TOTO
OUR PRESENTATIONOUR PRESENTATION

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ARIFUL ISLAMARIFUL ISLAM
ID : 151-15-4869ID : 151-15-4869

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Presented by
 Group 5
 ID:
 151-15-4869
 151-15-4856
 151-15-4861
 151-15-4883
 Dept: CSE
 DIU
Presnted to
 S.M. Safayet Ullah
 Lecturer
 Dept. of CSE
 DIU

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4
ALTERNATING CURRENT

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NODE
Branch : A branch represents a single element such as
voltage source or resistance etc.
 What is node?
Node : In a electric circuit a node is the point of
connection between two or more BRANCHES

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NODE

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Steps to Determine V (Voltage)
 Steps :
1. Firstly , we have to find out the nodes of the electrical
circuits.
2. Then , we have to apply KCL & Ohm’s law (V=IR)
3. Then , we have to write the equation.
4. At last, we have to solve the equation And find out V

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Mathematics

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Now we have to simultaneous Eq. 1 and 2. We can solve the
equations using any method and obtain the values of V1 and V2

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Shamsuzzaman ZihanShamsuzzaman Zihan
ID : 151-15-4861ID : 151-15-4861

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Norton’s Theorem
 A linear two-terminal circuit can be replaced with
an equivalent circuit of an ideal current source, IN,
in parallel with a resistor, RN.
– IN is equal to the short-circuit current at the terminals.
– RN is the equivalent or input resistance when the
independent sources in the linear circuit are turned off.

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Circuit Schematic:
Norton’s Theorem

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Definitions for Norton’s Theorem
Short-circuit current Isc is the current, i, when the load is a short circuit
(i.e., RL = 0Ω).
NSC II =

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Steps to Determine IN and RN
1. Identify the load, which may be a resistor or a
part of the circuit.
2. Replace the load with a short circuit .
3. Calculate ISC. This is IN.
4. Turn off all independent voltage and currents
sources in the linear 2-terminal circuit.
5. Calculate the equivalent resistance of the circuit.
This is RN.
 The current through and voltage across the load in
parallel with IN and RN is the load’s actual current and
voltage in the original circuit.

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Nazmul AhsanNazmul Ahsan
ID : 151-15-4856ID : 151-15-4856

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What is alternating Current(AC)?
 Alternating current (AC), is an electric current
in which the flow of electric charge periodically
reverses direction, An AC waveform can be
sinusoidal

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HISTORY OF ALTERNATING CURRENT
ALTERNATING CURRENT
18
William Stanley, Jr. designed one of the first practical
devices to transfer AC power efficiently between isolated circuits.
The AC power system used today developed rapidly after
1886, and included contributions by Nikola Tesla and Carl
Wilhelm Siemens.

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EQUATION

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EQUATION
Or
y = A sin (ωt + φ)

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EQUATION

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AC Current
The current flowing
through the circuit can
be calculated using
Ohms’ Law (V=IR) and
is usually measured with
an oscilloscope.
Notice that voltage and
current through the
resistor are in phase.

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Akash Ahmed Khan
ID : 151-15-4883ID : 151-15-4883

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RMS VALUES
ALTERNATING CURRENT
 Since voltage and current are always changing we need some way
of averaging out their effect.
 We use r.m.s values (root-mean-square)
 The r.m.s values are the DC values which give the same average
power output

25. 25ALTERNATING CURRENT

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AC in capacitors
ALTERNATING CURRENT
In an AC circuit, the current can continue to flow, as the
plates become alternately charged positively and negatively
For both AC and DC circuits, the voltage across the resistor
is related to the current by V=I.R
A similar relationship exists for a capacitor:

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Advantages
ALTERNATING CURRENT
 The single greatest advantage of alternating current is that AC
current can be transformed and DC current cannot be
transformed.
 It can be controlled by a wide range of components
eg.resistors,capacitors and inductors.
 This allows high-voltage electrical power to be distributed with
smaller wires and lower amperage.

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references
ALTERNATING CURRENT
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 http://www.teachersdomain.org
 http://www.peetvs.co.za
 http://www.sjsu.edu
 http://www.youtube.com
 http://www.wikipedia.com
 http://www.upscale.utoronto.ca
 NCEA A.S 3.6 Text Chapters 18-19
 Yrd. Doç. Dr. Levent Çetin/ alternatif akım

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THANKS FOR LISENTING……..
THE END