This lesson will introduce you to electrical circuits that combine series circuits and parallel circuits. This lesson will introduce you to electrical.

ELECTRICAL CIRCUIT ANALYSIS

• This lesson will introduce you to electrical circuits that combine series circuits and parallel circuits.

• You will also learn how to analysis this circuits to solve for unknown quantities

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By the end of this lesson, you will be able to:

What are we going to cover today?

Draw circuit analysis cards

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Apply Kirchhoff’s laws to comb circuitsAnalysis combination circuits

Homework

KVL & KCL Review https://www.youtube.com/watch?v=Z2QDXjG2ynU

CIRCUIT ANALYSIS CARDSS

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• whenever you analyse a circuit, you must convey the information and results in a circuit analysis card. CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1)Resistor (R2)Resistor (R3)

Resistor (RN)

Totals ..

CIRCUIT ANALYSIS STEPSS

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STEP 1a: Fill in any known quantities in your circuit analysis card

STEP 1b: Fill in any “buried” known quantities. These quantities are the ones you can assume at a glance from KLSTEP 2: Reduce any parallel element to a series equiv.STEP 3: Draw the circuit as a series equivalent circuit and calculate the total resistance by adding up the resistors.

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STEP 4: Use V = IR to find any missing variable if you are given any two out of three variables in a row of the card

STEP 5: According to KCL, all series resistors have the same current. Fill in these currents in the card.

STEP 6: Repeat STEP 4.

STEP 7: Use KVL to determine any unknown voltages.

STEP 8: Repeat STEP 4.

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sEx 1:Analyse the following circuit

Vo = 120. V

R1 = 5.00 W

R4 = 20.0 W

R2 = 10.0 W R3 = 15.0 W

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Step 1a:

CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1) 5.00

Resistor (R2) 10.0

Resistor (R3) 15.0

Resistor (R4) 20.0

Totals 120

Step 1b: can’t be done

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2 3 2 3

1 1 1R R R

1 110 15

W2 3R 6.0

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Vo = 120. V

R1 = 5.00 W

R4 = 20.0 W

R2-3 = 6.0 W

RT = R1 + R2-3 + R4 = 31.0 W

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CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1) 5.00

Resistor (R2) 10.0

Resistor (R3) 15.0

Resistor (R4) 20.0

Totals 120 31

Step 4: Use Ohm’s Law to find Io

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VI

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120I 3.87 A

31

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According to KCL: I1 = I2-3 = I4 = IT = 3.87 A

CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1) 3.87 5.00

Resistor (R2) 10.0

Resistor (R3) 15.0

Resistor (R4) 3.87 20.0

Totals 120 3.87 31.0

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s Step 6: Use Ohm’s Law to find V1 , V4

1 1 1

4 4 4

V R I 19.4 VV R I 77.4 V

CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1) 19.4 3.87 5.00

Resistor (R2) 10.0

Resistor (R3) 15.0

Resistor (R4) 77.4 3.87 20.0

Totals 120 3.87 31.0

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V3

2

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V 120 19.4 77.423.2 V

V 120 19.4 77.423.2 V

CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1) 19.4 3.87 5.00

Resistor (R2) 23.2 10.0

Resistor (R3) 23.2 15.0

Resistor (R4) 77.4 3.87 20.0

Totals 120 3.87 31.0

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2

3

23.2I 2.32 A

10.023.2

I 1.55 A15

CIRCUIT ANALYSIS CARD

Circuit Item V (V) I (A) R(W)

Resistor (R1) 19.4 3.87 5.00

Resistor (R2) 23.2 2.32 10.0

Resistor (R3) 23.2 1.55 15.0

Resistor (R4) 77.4 3.87 20.0

Totals 120 3.87 31.0

PRACTICE QUESTIONS

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SMART Response Question

1. A

HOMEWORKS

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Read pgs Questions