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.

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.

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

1/RT = 1/R1 + 1/R2 + 1/R3 1/RT = 1/100 Ω + 1/100 Ω + 1/100 Ω 1/RT = .01 Ω + .01 Ω + .01 Ω 1/RT = .03 Ω 1 = .03 Ω x RT 1/.03 Ω = RT 33.333 Ω = RT

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

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

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

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

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 + .25 Ω 1/RA = .55 Ω 1 = RA x .55 Ω 1/.55 Ω = RA 1.818 Ω = RA

1b. Calculate Total Resistance (RT) RT = R1 + R2 + RA + R6 RT = 3Ω + 2Ω + 1.818Ω + 25Ω RT = 31.818Ω Calculate Current V = I x R 120v = I x 3.818Ω 120v/3.818Ω = I 31.43 amps. = I

Calculate Power P = V x I P = 120 v x 31.43 amps. P = 3771.6 W

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

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