Electrical Circuits

Targeted Skills for Circuits

1.Define: voltage, current, resistance, power, and Ohm's Law.

2. Qualitatively analyze series, parallel and combination circuit problems

Electrical CircuitsTargeted Skills for Circuits

3. Draw schematic diagrams.

4. Construct a circuit and properly wire an ammeter and voltmeter.

5. Solve series, parallel and combination circuit problems.

Draw orientations that result in the bulb lighting.

Draw the inner workings of a light bulb.

Introduction Lab – Post Lab

Conductors and InsulatorsDefinitions:

Conducting Path

Polarity

Definitions

Conducting Path

Polarity

Types of Connections:

Series Connection

Parallel Connection

Schematic Diagram Elements

Wire

Resistor

Bulb

Schematic Diagram Elements

Battery

Switch

PowerPolarity

Definition

Equations:

Bulb brightness - PreLab

Bulb brightness – Post Lab

Qualitative Circuit Analysis

Example #1A 60 W light bulb is accidentally left on in the attic

when you put Christmas ornaments away. If the bulb is left on until the following Christmas and doesn’t burn out, how much energy does the bulb use in the intervening year?

G: P=60 W, T= 1 yr, $= $0.08 per kW • hr

U: Cost per year = _____

E: P = W/T

S: See Overhead

S: See Overhead

If the electric company charges $0.08 per kW • hr, how much did you forgetfulness cost your parents?

MetersDefinitions

Current

Conventional

Electron Flow

Meters

Ammeter

Voltmeter

Meters

Series Connection

Parallel Connection

Schematic Diagram Elements

Ammeter

Voltmeter

Bulbs Reading Lab - PreLab

Definitions

Power

Bulbs Reading Lab - PostLab

Kirchoff’s Laws

Loop Law

Kirchoff’s Laws

Junction Law

Ohm’s Law PreLab

Purpose

Hypothesis

Sketch

Ohm’s Law PreLab

You will have the entire class period to collect and begin your data analysis. The completed lab report is due the next class period. You will be given 20 minutes to write your in-class conclusion at the first of the next class period. You may use your lab report to assist you in your writing as well as the teacher provided copy of the conclusion format sheet (example removed). The lab report and conclusion will be collect after the 20 minute writing period.

Series and Parallel Lab - PreLab

Ohm’s Law Post Lab

Series and Parallel Lab - PostLab

Equivalent Resistance

Series Circuit

Equivalent Resistance

Parallel Circuit

Equivalent Resistance

Compound Circuit

Example #2A battery charger is connected to a dead battery

and delivers a current of 8.0 A for 3.0 hrs, keeping the voltage across the terminals at 12 in the process.

G: P=60 W, T= 1 yr, $= $0.08 per kW • hr

U: Cost per year = _____

E: V = IR, P = W/T

S: See Overhead

S: See Overhead

How much energy is delivered to the battery?

What is the internal resistance of the battery?

Example #3A circuit is composed of a 24 V battery and four

resistors, whose resistances are 110 , 180 , 220 , and 240 .

G: V = 24 V

U: Iseries = _____ , IPARALLEL = _____

E: V = IR, Rseries= R1 + R2 …,

Rparallel= 1/ R1 + 1/ R2 + …

S: See Overhead , S: See Overhead

Find the total current supplied by the battery if the resistors are connected in parallel.

Find the total current supplied by the battery if the resistors are connected in series.

Example #4Complete the VIRP chart for a 2 and a 6

resistor wired in series with a 12 V battery.

Voltage Current Resistance Power

1

2

Total

Example #4For the 2 and a 6 resistor wired in series with a

12 V battery. Draw the schematic diagram

Example #5Complete the VIRP chart for a 2 and a 6

resistor wired in parallel with a 12 V battery.

Voltage Current Resistance Power

1

2

Total

Voltage Current Resistance Power

1

2

Total

Example #5For the 2 and a 6 resistor wired in series with a

12 V battery. Draw the schematic diagram

Example #6Complete the VIRP chart for for the circuit shown to

the right. Let V = 16 V, R1 = 4 , R2 = R3 = 8

Voltage Current Resistance Power

1

2

Total