Aim: What are 5 main forms of Energy?

Do Now: 1. What is work?

2. What are units of work?

Homework: Have a great weekend!!!

Date: 11/16/2007 Friday

What is Energy? • The ability to do work

• Measured in Units of Joules

the energy found in the bonds that hold atoms together

• When bonds are broken, energy is released

• Example: fossil fuels (oil, gas, coal), food, a battery

1. Chemical:What are the

5 main forms of Energy?

2. Heat:

• Associated with the internal motion of atoms

• Causes change in temp. & phase changes

• Usually results from Friction

Energy associated with moving charges called electrons

Examples: electricity, light, x-rays…

3. Electromagnetic:

4. Mechanical:

energy associated with motion

Examples: Sound, moving water, wind…

5. Nuclear:

• energy associated with the

nucleus of an atom

Ex) Radioactive Substances have unstable nuclei that breakdown

• When the nucleus splits (fission) heat & light are released

• When hydrogen nuclei collide & fuse to form helium fusion occurs (Sun)

• The most concentrated form of energy

Aim: How does Potential Energy compare to Kinetic Energy?

Date: 11/19/2007 Monday

Do Now: 1. Take out homework.

2. Handout

Homework: Read pgs 128-133 & Define the 9 Vocabulary Words on the top of pg 148

(Using Vocabulary)

What is Potential Energy?

• Stored energy or energy of position

• Example: Stretched rubber band, or compressed spring

• Gravitational Potential Energy

G.P.E. = Weight X HeightWhat is

weight?

What happens to GPE as

weight increases

?

What happens to GPE as

height increases?

What is Kinetic Energy?

• Energy of Motion

• K.E. = mass x velocity2

2

What happens to K.E as mass increases?

What happens to

K.E as velocity

increases?

What is velocity?

Which Rubber Band has Greater Potential Energy?

Which picturedemonstratesPotential Energy& what picture shows KineticEnergy?

P. E.

K.E.

Why doesn’t the still ball have Energy at the bottom of the

hill?

                                                                                                                                                                  

Aim: Lab – What is the difference between potential & kinetic energy?

Do Now: Handout (Ball: K.E. vs. P.E.)

Homework: Complete Lab questions.

Date: 11/20/2007 Tuesday

1. Where is Potential Energy the greatest?

2. Where is Kinetic Energy the greatest?

3. Where is the leastK.E.?

4. Where does K.E. = P.E.?

Aim: 1. What is the Law of Conservation of Energy?

2. How did you do on your Work & Machines Exam?

Do Now: Take out homework (lab)

Homework: Have a Happy & Safe Thanksgiving!!! Study for quiz on Energy (Next Tuesday)

Date: 11/21/2007 Wednesday

What is the Law of Conservation of Energy?

• Energy can neither be created or destroyed by ordinary means

• It can only change from one form to another(During the change some energy is always converted to heat.)

12 3 4

51

1. Where is Potential Energy the greatest?

2. Where is Kinetic Energy the greatest?

3. Where is the leastK.E.?

4. Where does K.E. = P.E.?

12 3 4

5

0.10 N0.22 N

Inclined Plane35 N2m

50 N

DE/DR = 2m/1m = 2

FE X DE = 35 N X 2 m = 70 J

FR X DR = 50 N X 1 m = 50 JWoutput / Winput X 100 = 50/70 X 100 = 71%

Aim: What are energy conversions?

Do Now: Compare Potential to Kinetic Energy.

Homework: Study for tomorrow’s Quiz (Energy)

Date: 11/26/2007 Monday

What are energy conversions?

Example:

• Chemical energy in gasoline is transformed into mechanical energy in an automobile engine.

• Energy, in the form of heat, is almost always one of the products of energy transformations.

P.E. is converted into K.E. &K.E. is converted into P.E.

A

B

A-BB-CC-DD-EE-F

P.E. decreases as K.E. increases

P.E. decreases as K.E. increases

P.E. decreases as K.E. increases

P.E. increases as K.E. decreases

P.E. increases as K.E. decreases

Chemical Energyto Light & HeatEnergy

Mechanical Energyto MechanicalEnergy (Sound)

ElectromagneticEnergy (Light)to ChemicalEnergy

MechanicalEnergy toElectromagneticEnergy (Light) &Heat Energy

Aim: What is the difference between non- renewable & renewable energy resources?

Do Now: Prepare for quiz.

Homework: pg 512 (1-14) Use complete sentences.

Date: 11/27/2007 Tuesday

Energy Quiz(Choose: Chemical, Heat, Electromagnetic, Mechanical,

or Nuclear for your answers)

1. Sound is a type of _________ energy.

2. When atomic bonds are broken, _______ energy is released.

3. Energy associated with motion is called ______ energy.

4. The internal motion of atoms is called _______ energy.

5. Light & electricity are forms of _________ energy.

• Fossil fuels: coal, oil, petroleum, and natural gas

• Considered non-renewable because humans use them faster than they can be made

(they take millions of years to make)

• These are a major source of energy in the U.S.

Non-Renewable Energy Sources

• When fossil fuels burns, they release carbon dioxide gas.

• Increases in CO2 creates the “Greenhouse Effect” which is associated with Global Warming.

• Global Warming melts polar ice caps & raises water levels leading to flooding & strange weather patterns.

• The burning of coal also contributes to making sulfuric & nitric acids which make acid rain.

Problems WithNon-Renewable Energy Source

• Transport of fossil fuels has also been associated with oil spills that directly kill wildlife or damage the wildlife’s environment.

Problems WithNon-Renewable Energy Source

• Examples: Sunlight (a major source of energy for the earth), wind, falling water, tides, geothermal, & biomass

• Each of these create very little or no pollution

• Wood (biomass) can be considered a renewable energy resource as long as trees are replanted.

Renewable Energy Source

• Photovoltaic cells convert solar energy directly into electrical energy. Ex) solar calculator

• The heat from the Sun can also be used to boil water to create steam to turn a turbine & make electricity

Solar Energy

• As the Sun strikes Earth, the atmosphere is unevenly heated creating wind.

• Wind energy can be used to turn the turbines of a generator producing electricity.

Wind Energy

• Moving water can turn a turbine to create electricity.

• Water can be heated by burning biomass (wood, manure…), geothermal energy, or the sun to create steam.

• Steam can also turn a turbine to create electricity.

Hydroelectric Energy

• In the middle of the earth is hot liquid rock called magma.

• The heat from inside Earth, can be used to heat homes or boil water to create steam that drives turbines.

Geothermal Energy

Aim: How is matter affected by heat?Do Now: 1. Take out homework.

2. What is matter?

3. What is heat?

Homework: Read pgs 260-265 Answer Self-check Questions (1-3) on pg 265.

Date: 11/28/2007 Wednesday

What is matter?

• Anything that has mass & takes up space

(volume)

What are 3 phases of matter & their properties?

• Have a definite volume & shape

• Particles are tightly packed together & vibrate in place (least K.E.)

• Have a definite volume, but take the shape of its container

(particles can slide past each other: attractive forces are weaker)

1. Solids:

2. Liquids:

What are 3 phases of matter & their properties?

• Have no definite volume or shape

• Particles are very far apart

& move the fastest• Attractive forces = weakest

3. Gases:

• No definite shape or volume• Exists in very high temps. (ex)

stars & lightning)• Charged particles

4. Plasma:

What is

heat?

• Thermal Energy

• Caused by the internal motion of particles of matter

• Always flows from areas of

Hot (warm) to Cold (cool)

Until both areas reach the same temp.

• Addition or removal causes phase changes to occur (physical changes of matter from one state to another)

Where will the heat flow?

A. 20º C B. 15º C

C. 38º C D. 65º C

Which has the most heat energy?

Aim: How does heat affect temperature?

Do Now: 1. Take out homework.

2. Are phase changes physical or chemical changes? Why?

Homework: Read pgs 254-259 & Answer self-check questions (1-5) on pg 259.

Date: 11/29/2007 Thursday

What is temperature?

• The measure of the motion (avg. kinetic energy) of molecules in a substance

When does water have a greater K.E.at 50º C or 70ºC?

How does heat effect the temperature of a substance?

1. When heat is added avg. K.E. increases (molecules move faster & spread apart) & temp. increases

2. When heat is removed avg. K.E. decreases (molecules move slower & usu. closer together) & temp. decreases

• Most substances expand when heated & contract when cooled.

• Water is an exception, expanding when changing to ice.

• Temperature also affects the solubility of some substances in water.

Phase Change Movie

What are some important temperatures?

Celcius Fahrenheit KelvinFreezing

pt. of water

Boiling pt. of water

Body Temperature

0º C

100º C

37º C

32º F

212º F

98.6º F

273 K

373 K

AbsoluteZero -273º C 0 K

310 K

How can you find the amount of heat gained or lost by a sample of water?

Heat gained or lost =

Mass x ΔT x Specific Heat

(Δ = change)

Units = calories

Specific Heat =

The ability of a substance to absorb heat

1) The temperature of a 10 gram sample of water increases from 20º C to 40º C. How much heat energy did it gain?

Heat gained = Mass x ΔT x Specific Heat

Heat gained = 10 g x 20º C x 1 cal/g. º C

Heat gained = 200 calories

2) The temperature of a 5 gram sample of water decreases from 50º C to 45º C. How much heat did it lose?

Heat gained = Mass x ΔT x Specific Heat

Heat gained = 5 g x 5º C x 1 cal/g. º C

Heat gained = 25 calories

Aim: What are various types of phase changes?

Do Now: 1. Take out note-packet & homework.

2. What is absolute zero?

Homework: Study for next Thursday’s Exam on Energy & Heat.

Handout (phase changes)

Date: 11/30/2007 Friday

Absolute Zero:K.E. = ZeroNo Molecular Motion

What arethe varioustypes of phase changes?

S L G

Adding Heat

Removing Heat

sublimation

deposition

melting

freezing condensation

vaporization

sublimation example: Dry Ice (solid) changes to CO2 (gas)

Heat Energy

Phase Change Movie Clip - Yahoo! Video

What is a heatingcurve?

A graph that shows how the physical state & temperature of a substanceis affected by the additionof heat over time

Physical State of the Water

1. Between Points A & B___________________

2. At Point B_____________________________

3. Between Points B & C___________________

4. At Point C____________________________

5. Between Points C & D__________________

6. At Point D____________________________

7. Between Points D & E___________________

8. At Point E_____________________________

9. Between Points E & F___________________

Solid

Liquid

Gas

Solid & Liquid

Liquid & Gas

Solid

Liquid

Liquid

Gas

Aim: 1. What are differences between insulators & conductors of heat? 2. What are 3 methods of heat transfer?

Do Now: 1. Take out handout & note-packet

2. How does an ice cube form?

Homework: Read pgs 266-270 & answer self-check questions (1-5) on pg 270

Date: 12/3/2007 Monday

Type of phases change Heat change

Freezing(liquid to solid)

Melting(solid to liquid)

Vaporization(liquid to gas)

Evaporation(liquid to gas)

Sublimation(solid to gas)

Condensation(gas to liquid)

Deposition(gas to solid)

Heat removed

Heat added

Heat added

Heat added

Heat added

Heat removed

Heat removed

Energy Changes1. Every Diagonal 2. Every Plateau

(Phase Change)

Temperature stays the same as heatenergy is added orremoved

Temperaturechanges as heatenergy is added orremoved

What are insulators of heat?

• Substances that don’t conduct heat easily

• Examples: Glass, Wood, plastic,

rubber                       

What are conductors of heat?

• Substances through which heat transfers easily

• Examples: Copper, Silver,

Iron, Aluminum

What are 3 methods of heat transfer?

1) Conduction

2) Convection

3) Radiation

What are 3 methods of heat transfer?

1) Conduction:

• Heat transfer occurs by

collision of particles (direct contact)

• From warmer particles to cooler particles

What are 3 methods of heat transfer?

2) Convection:

• Heat transfer through Liquids & Gases through convection currents

• Ex. creates winds & occurs in the mantle of the earth

Cool air sinks(Its more dense)

(Its less dense)

molecules move faster & spread apart becoming

less dense anything less dense rises

Convection Current

molecules move slower & closer

together becoming more dense, anything

more dense sinks

What are 3 methods of heat transfer?

3) Radiation:

• Heat transfer by infrared waves through empty space (a vacuum)

• Ex) The sun radiates heat

Aim: Lab: What are examples of conduction & convection?

Do Now: 1. Take out homework.

2. Brainpop: States of Matter

Homework: Study for Quiz on Heat

Date: 12/4/2007 Tuesday

Aim: 1. Take & Go over Quiz 2. Review: What do you know about

Energy & Heat?Do Now: Prepare for Quiz.

Homework: Bring a Pencil & Study for Exam on Energy & Heat (Part II)

Date: 12/5/2007 Wednesday

Name___________ Quiz1. Heat never flows from areas of ___________ to

___________. (Hot to Cold, or Cold to Hot)2. ___________have particles that are close together

& move the slowest. (Solids, Liquids or Gases)3. ___________Phase changes are (chemical/physical)

changes of matter from one state to another.4. ___________is the transfer of heat energy by

molecular (or direct) contact. (Conduction or Induction)

5. ___________The condensing point of a substance is equal to the __________ point. (Boiling point or Freezing point)

6. ___________ is the measure of the average kinetic energy of a substance. (Heat or Temperature)

7. ___________During condensation (gas to liquid) is energy absorbed or released?

8. ___________A phase change directly from a solid to a gas is known as ____________. (Melting, Condensation, Sublimation, or Deposition)

9. ___________When a substance is heated, its molecules vibrate (move):

A) Slower & closer together

B) Slower & farther apart

C) Faster & farther apart

D) Faster & closer together

10. ___________These pictures demonstrate a process of heat transfer known as________. (Conduction, Convection, or Radiation)

Aim: Exam: What do you know about Energy & Heat? (Part (II)

Do Now: Take out pencil, put up binders & Prepare for Exam.

Homework: Bring a Pencil & Study for Exam on Energy & Heat (Part I)

Date: 12/6/2007Thursday

Aim: Exam: What do you know about Energy & Heat? (Part (I)

Do Now: Take out pencil, put up binders & Prepare for Exam.

Homework: Have a good weekend!!!

Date: 12/7/2007Friday

Name___________ Quiz1. ___________ is the energy trapped within

the bonds that hold atoms together.

2. ___________ is the most concentrated form of energy.

3. ___________ are units used for energy.

4. ___________is energy associated with moving charges (electrons).

5. ___________is the ability to do work.

6. ___________ is the type of energy associated with the internal motion of molecules.

7. ___________is energy of position.8. Potential Energy depends upon the

weight X _________ of an object.9. The Law of ___________ of __________

states that energy can’t be created or destroyed by ordinary means it can only change from one form to another.

10. Where is P.E. the greatest?

11. Where is K.E. the greatest?

12. Where does K.E. = P.E.?

Answer questions 10-12 with the letter(s)in the diagram to the left.