1. Date DRILL V = I x R is _________ law. Joule’s law is___________.
What schematic symbol is this?
_________________________
The flow of electrons in a conductor is called
__________________.
Conductors have __________electrons.
Insulators have ___________electrons.
Electrons in a circuit flow through the __________
and the _______________ from the __________
terminal of the power source to the ___________
terminal of the power source.

2. Date DRILL
V = I x R is __Ohm’s_______ law.
Joule’s law is _ P = V x I _____.
What schematic symbol is this?
_AC Power Source_____________
The flow of electrons in a conductor is called
__Current_________.
Conductors have __free____ electrons.
Insulators have __bound____ electrons.
Electrons in a circuit flow through the Conductor
and the ___Load________ from the negative__
terminal of the power source to the positive
terminal of the power source.

3. Resistance Calculations
U3e-L3
Resistance Calculations
Calculate the resistance in the following circuit:
100 Ω
100 Ω
100 Ω
R3=
R2=
R1=

4. 1/RT = 1/R1 + 1/R2 + 1/R3
1/RT = 1/100 Ω + 1/100 Ω + 1/100 Ω
1/RT = .01 Ω Ω Ω
1/RT = .03 Ω
1 = .03 Ω x RT
1/.03 Ω = RT
Ω = RT

5. Draw a schematic for this circuit
25Ω 5Ω 4Ω
10Ω
120v 3Ω 2Ω

6. R6= 25Ω
R3= 5Ω
120v
R5= 4Ω
R4= 10Ω
R2= 2Ω
R1= 3Ω

7. 1. Calculate the RT
2. Calculate the Current
3. Calculate the Power

9. A Start by identifying any parallel segments R6= 25Ω R3= 5Ω 120v

10. 1a. Calculate parallel segments
1/RA = 1/R3 + 1/R4 + 1/R5
1/RA = 1/5 Ω + 1/10 Ω + 1/4 Ω
1/RA = .2 Ω + .1 Ω Ω
1/RA = .55 Ω
1 = RA x .55 Ω
1/.55 Ω = RA
1.818 Ω = RA

11. 1b. Calculate Total Resistance (RT)
RT = R1 + R2 + RA + R6
RT = 3Ω + 2Ω Ω + 25Ω
RT = Ω
Calculate Current
V = I x R
120v = I x 3.818Ω
120v/3.818Ω = I
31.43 amps. = I

12. Calculate Power
P = V x I
P = 120 v x amps.
P = W

13. HOMEWORK
120v
10 amps.
Schematic
Resistance = ?
Power = ?

15. HOMEWORK What type of power supply (AC or DC)? ___________
2. What is the voltage? _____________
3. What is the frequency? ___________ Hz.
100 v
50 v
0 v
-50 v
-100 v
0.3 sec
0.1 sec
0.2 sec