Test Review Test Review Chapter 16 and 17 Chapter 16 and 17

Major ConceptsMajor Concepts

- CircuitsCircuits- Parallel vs SeriesParallel vs Series- How to determine current, voltage, resistance and the How to determine current, voltage, resistance and the

definition of eachdefinition of each- What happens to the circuit when bulbs burn outWhat happens to the circuit when bulbs burn out

- VocabularyVocabulary- Multimeter, insulators, pot dial, ETC. Multimeter, insulators, pot dial, ETC.

- MagnetsMagnets- Attraction and Repulsion Attraction and Repulsion - Atoms within a magnetAtoms within a magnet

- Compass Compass - Geographic North and South, Magnetic North and SouthGeographic North and South, Magnetic North and South- How would the dial change when a magnet is near by How would the dial change when a magnet is near by

ElectromagnetsElectromagnets– How do they work? How do they work? – Right-hand ruleRight-hand rule

Motors and generatorsMotors and generators– How do they work? How do they work? – What is the major difference?What is the major difference?

Renewable and Non-renewable Renewable and Non-renewable resourcesresources– Types, sources, Types, sources, – What do we use the most for electricity?What do we use the most for electricity?

Electrical PowerElectrical PowerCurrent x Voltage = Power (P=IV)Current x Voltage = Power (P=IV)

If you use a 1,500-watt heater for 3 hours. How If you use a 1,500-watt heater for 3 hours. How many kilowatt-hours of electricity did you use? many kilowatt-hours of electricity did you use?

**Remember!! Kilowatt is 1000 watts = 1000J/s**Remember!! Kilowatt is 1000 watts = 1000J/s

Compass Compass

If I place a magnet at different points onthe compass what will happen?

Earth is an example of what type of magnet?

From lab page: 65 Question B

What is magnetic declination ?

ElectromagnetsElectromagnets

Current has the ability to Current has the ability to create the poles of the create the poles of the electromagnetelectromagnet

Right-hand ruleRight-hand rule: If you place : If you place your fingers in the path of the your fingers in the path of the current then your thumb will current then your thumb will point in the direction N. point in the direction N.

There are two ways to There are two ways to increase the current in a increase the current in a simple electromagnet:simple electromagnet:1.1. Apply more voltage by Apply more voltage by

adding a second battery.adding a second battery.2.2. Add more turns of wire Add more turns of wire

around the nail.around the nail.

But there may be something But there may be something else!else!

What should be What should be happeninghappeningLab time! Lab time!

Current Current

Series Series

SAME THROUGHOUTSAME THROUGHOUT

*The current takes *The current takes one pathone path

I = 6V/3OhmsI = 6V/3Ohms

I = 2 ampsI = 2 amps

ParallelParallel

DIFFERENT DIFFERENT THROUGHOUTTHROUGHOUT

The current can The current can take different take different paths to each paths to each

resistorresistor I = 12V/3Ohms= 4AI = 12V/3Ohms= 4A

I = 12V/3Ohms = 4AI = 12V/3Ohms = 4A

VoltageVoltageSeries Series

Different ThroughoutDifferent Throughout- Voltage drops at Voltage drops at

each resistor each resistor (potential energy (potential energy lost) lost)

- Need to know total Need to know total voltagevoltage

V1= 2A x 1 Ohms = 2 voltsV1= 2A x 1 Ohms = 2 volts

V2 = 2A x 2 Ohms = 4 voltsV2 = 2A x 2 Ohms = 4 volts

ParallelParallel

Same ThroughoutSame Throughout

The amount of The amount of potential energy potential energy going to each bulb going to each bulb remains the same remains the same because of this because of this awesome circuitawesome circuit

Voltage = 12 volts at Voltage = 12 volts at each branch each branch

Resistance Resistance

Series Series

- Resistance is a total Resistance is a total amount amount

- Add up all the resistors Add up all the resistors to get total resistanceto get total resistance

RRtt = R = R11 + R + R22

RRtt = 1 Ohm + 2 Ohm = 3 = 1 Ohm + 2 Ohm = 3 Ohms Ohms

ParallelParallel

Resistance DOES NOT add Resistance DOES NOT add up! up!

The resistance you calculate The resistance you calculate for the entire circuit is for the entire circuit is basically an average basically an average

Total Votage/Total Current = Total Votage/Total Current = Total Resistance Total Resistance

V/I = Total R V/I = Total R

12 V/ 8A = 1.5 Ohms 12 V/ 8A = 1.5 Ohms

Motors Motors

To cause the rotor to turn in a counter-clockwise direction, the north pole of a magnet should be placed at position:

Remember:

Motors USE ELECTRICITYGenerators MAKE ELECTRICITY

Require 3 Things: 1. 2. 3.