unit 1: energy power point science 8

Unit 1: ENERGY

1

Stop Monkey-N-ing around and

Go Green already! P.S. I’m Mookie the

Monkey

What is ENERGY? Energy is the ability

to do _______!Work!

2

Work occurs when a _____ causes an

object to _____ in the same direction as

the force.!

move!force!

3

FORMS OF ENERGY Both basic states of energy,

Kinetic and potential, can exist in many forms!!

The total ________ energy of the particles in

matter. (molecular motion)!

Kinetic!THERMAL (HEAT)

6

A type of mechanical energy. It is the

energy produced when objects ________. Ex: tuning fork, bell!

vibrate!

SOUND

7

Energy with which ______ objects perform work.!

Ex: Wind, flowing water, using a hammer!

moving!

MECHANICAL

8

A form of energy produced by

the ________ of ________!

movement!

ELECTRICITY

electrons!9

Energy STORED in chemical ____ that can be released. Ex: food, fossil fuels, battery acid!

bonds!

CHEMICAL

10

Stored energy due to a change in the shape of an object. Ex: !

_______________!A stretched rubber band!

STORED MECHANICAL ENERGY:

11

STORED MECHANICAL ENERGY:

12

A form of _______ energy that moves in a ______.!

Ex: lamp, stars!

radiant!LIGHT

wave!

13

All forms of energy that come from the ______.!SUN!

SOLAR ENERGY

14

Energy STORED in the ________ (center) of an atom.! Ex: nuclear bombs!

nucleus!

NUCLEAR

15

Heat energy STORED within the _____. Ex:!

Volcanic eruptions, geysers!Earth!

GEOTHERMAL (HEAT)

16

All forms of energy can be classified as Kinetic or potential. The two basic states of energy. So, what’s

the difference?! 17

1) Potential energy is stored energy due to

and object’s _____________!Position!

POTENTIAL ENERGY

21

2) An object that is lifted from its position on Earth

has __________ potential Energy which depends on

______ and mass!

gravitational!

POTENTIAL ENERGY

height!22

3) Massive objects have _____

potential energy than less massive

objects!

more!

POTENTIAL ENERGY

23

4) An object at a higher elevation will have

_____ potential energy than an object at a

lower elevation!

more!

POTENTIAL ENERGY

24

1)   Kinetic is energy of !

___________!Motion!

KINETIC ENERGY

25

2) Kinetic depends on the _____ and the

_______ of an object. !

MASS!

KINETIC ENERGY

SPEED!

26

3) Faster objects have ____

kinetic energy than slower

objects.!

More!

KINETIC ENERGY

27

REVIEW QUESTONS:

A

B

C D

WHICH SKIIER HAS THE GREATEST KINETIC ENERGY?

WHICH SKIIER HAS THE GREATEST POTENTIAL ENERGY?

A

B

C D

Do you remember the LAW OF

CONSERVATION OF MASS AND ENERGY?!

ENERGY TRANSFORMATIONS

30

Law of Conservation of ENERGY: (same for mass)

Mass/ NRG ____________ Mass/ NRG ______________

Mass/ Energy can only __________

Can’t be made Can’t be destroyed

Change form!!!

DURING ENERGY CHANGES, IF ONE BODYIS LOSING ENERGY, THE OTHER IS _______ ENERGY:

THE WAVE LOSES ENERGY:

THE SAND GAINS ENERGY

Gaining

THE WAVE LOSES ENERGY:

THE SAND GAINS ENERGY

DURING ENERGY CHANGES, IF ONE BODYIS LOSING ENERGY THE OTHER IS GAINING ENERGY:

DURING ENERGY CHANGES THE TOTAL ENERGY REMAINS THE SAME

ENERGY ALWAYS FLOWS FROM HIGH TO LOW (source to sink)

THE ENERGY WILL FLOW FROM:

THE FLAME TO THE FINGER

ICE

ENERGY WILL FLOW FROM

THE FINGER TO THE ICE

THE LIQUID LOSES ENERGY AS THE ICE GAINS ENERGY

WHEN WILL THE EXCHANGE OF ENERGY STOP? WHEN EQUILIBRIUM IS REACHED

THE LIQUID AND THE ICE REACH THE SAME TEMPERATURE

Very often during the energy transformation process, some ____ energy is

produced due to friction. This is wasted energy and is lost to the environment.!

heat!

UNUSABLE ENERGY:

39

Example: A !television changes !electrical NRG! into light and! sound NRG!


40


41

Do Now: Focused Free Write What is different about how each of the three popcorns? How were they made? Explain!

Methods of Energy Transfer

Energy moves from regions of _________ concentration to ________ concentrations of energy.

high

low 44

_______ To _______

Source

sink

There are 3 methods of Energy Transfer  Radiation  ConDuction  ConVection

ConDuction

Explanation of Transfer

Direct contact (touch) Molecule To Molecule

-Conduction is a form of heat transfer by direct _______ of molecules!

contact!

49

-Conduction occurs fastest in _______ !solids!

Best Medium for energy transfer

50

-_______ are the best conductors of he heat energy. !

metals!

51

Examples  Touching a hot surface  Electricity

Conduction lab:

Con ection

Explanation of Transfer Energy transfer Due to Density differences

-Convection is a form of heat transfer that occurs by up and down motions of a _______ due to differences in ______ !

fluid!

density!56

-occurs ONLY in _____ which are liquids and gases! !

fluids!

Best Medium for energy transfer

57

Examples  Hot air or water rising  Volcanoes  Lava lamp

convection

 Radiatio

Explanation of Transfer Electromagnetic (EM) waves that move Through a vacuum (empty space)

-radiation is the transfer of heat in _____.!waves!

62

-Electromagnetic radiation travels at the speed of ______.!

light!

63

Best Medium for energy transfer No medium needed

Examples Gamma X-rays UV Visible Infrared Microwave radio

1. HEAT: the energy of moving __________ !particles!

HEAT NOTES

66

2. HOT OBJECTS contain __________ heat than than cold ones !

more!

HEAT NOTES

67

3. All objects above __________ contain heat!Absolute zero!

HEAT NOTES

68

4. Heat always flows from ______ objects to ______ objects until the objects reach _____ temperature. !

hotter!

HEAT NOTES

cooler!

same!69

5. The greater the difference in temperature between the two objects, the _________ heat is transferred.!

faster!

HEAT NOTES

70

HOW IS HEAT TRANSFERRED BETWEEN

OBJECTS?

71

Heat Transfer at Work

Name that type of heat transfer!

Conduction!

Convection!

Radiation!

73

Heat Transfer across the globe  http://www.classzone.com/books/earth_science/terc/content/visualizations/es1705/es1705page01.cfm

Specific Heat Quantity of heat needed to raise

One gram of any Substance by 1 degree Celsius

Specific Heat The higher the Specific heat… The more energy is needed to raise the temperature

Read the Did you know

box!!!

Measuring Specific Heat Energy can be measures in many different ways. Typical units include:

____________________, _________________, & ___________________

Joules Watts calories

The term “Joule” is named after English Scientist James Prescott Joule who lived from 1818 to 1889. He discovered that Heat is a type of Energy! 1,000 joules =1 kilojoule = 1 Btu

PHASES OF Matter:

Matter is anything made of atoms and molecules.

B) LIQUID

A) SOLID

C) GAS

Motion How is it Does it have Volume? (Kinetic bonded? A definite energy) shape? Little K.E. Molecules vibrate

Strong yes yes

More K.E. Molecules move freely

Not bonded rigidly

no yes

Most K.E. Molecules move fast

Not bonded

no no Gas

Liquid

Solid

What are the changes of phase called?

solid liquid

liquid gas

FREEZING

MELTING

VAPORIZATION

CONDENSATION

2. ENERGY IS RELEASED (lost) DURING:

SOLID LIQUID

GAS LIQUID

FREEZING

CONDENSATION

from higher K.E. to lower K.E.

3. ENERGY IS ABSORBED (gained) DURING:

SOLID LIQUID

GAS LIQUID

MELTING

VAPORIZATION

from lower K.E To higher K.E.

Latent heat

Energy stored during a phase change is called

__________________

No change in temperature

87

TAKE OUT YOUR EARTH SCIENCE REFERENCE TABLES

88

temp 0C

100

Heating Curve of Water

HEAT ENERGY ADDED

0 MELT

FREEZE

VAPORIZATION

CONDENSATION

STEAM

WATER

ICE

(Joules)

MELTING / FREEZING

+ 334 J/gram Energy is absorbed

Energy is released

00 C 00 C - 334 J/gram

1000 C 1000 C

+2260 J/g Energy is absorbed

Energy is released

VAPORIZATION/ CONDENSATION

-2260 J/g

1. Which phase changes release energy?

2. Which phase changes absorb energy?

3. Which phase has the most K.E.?

GAS (STEAM)

freezing & condensation

Vaporization & melting

Waves:

Waves are disturbances that transfer energy from place to place.

If you throw a stone into a pond, circular waves move along the

surface since some of the stones kinetic energy was transferred.

Waves:

The substance through which waves travel is called a medium. This can be

solid, liquid or gas.

Light does not need a medium it can travel through empty space called a

vacuum.

Waves: There are two types of waves: Transverse and Compressional.

Compressional

Transverse

Sound Energy: Sound waves are compressional and they need a medium to travel through. When sound travels through air its vibrates the air molecules until it reaches your ear and then it vibrates the bones and tissues of your ear.

Sound Energy: Sound waves are much slower than light waves. This is why you see lighting before your hear thunder. Light waves are transverse.

The Earth is always trying to achieve Equilibrium Energy is constantly being re-distributed flowing from source to sink

The Earth Receives Energy from two sources:

Radioactive

Energy CORE

All matter radiates some _____________ _____________ Electromagnetic

Energy

The sun emits energy in _____ wavelengths of the electromagnetic spectrum

ALL

ELECTROMAGNETIC SPECTRUM: REFERENCE TABLE PAGE 14

Increasingwavelength

Violet Blue Green Yellow Orange Red

visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4

gamma X ray Ultra violet

Infrared Microwaves

Radio waves

Decreasingwavelength



visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4


Infrared Microwaves

Radio waves


Each type of energy differs

in its __________ wavelength

A wavelength is the distance between two crests of the wave.

Frequency is defined as a number of cycles per unit time.

The Sun gives off light and heat in the form of _________________ and __________________ electromagnetic energy.

VISIBLE

UV

However, the short wavelengths (dangerous UV radiation) are mostly absorbed by the ozone so they don’t reach earth’s surface

OZONE

GAMMA

The Ozone layer is found in the _________________ layer of the atmosphere.

stratosphere



visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4


Infrared Microwaves

Radio waves


SHORT WAVE LENGTHS ARE MOSTLY ABSORBED by THE OZONE IN THE STRATOSPHERE gamma,

OZONE

X-RAYS




visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4


Infrared Microwaves

Radio waves


SHORT WAVE LENGTHS ARE MOSTLY ABSORBED by THE OZONE IN THE STRATOSPHERE gamma, x-rays,

OZONE

UV




visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4


Infrared Microwaves

Radio waves


This energy is absorbed by Earth’s surface, which in turn reradiates the energy in the form of heat called ________________ radiation

infrared

OZONE

VISIBLE LIGHT : PASSES THROUGH THE ATMOSPHERE WITH THE GREATEST INTENSITY




visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4


Infrared Microwaves

Radio waves


Heat energy that

Earth re-radiates

Sun emits all

wavelengths Infrared:

How does too Much contribute to Global warming?

CO2 H20 VAPOR

METHANE GAS

INFRARED

CO2

CO2 absorbs infrared

Interactions between Electromagnetic Energy & The Environment:

1.

2.

3.

4.

5.

ABSORBTION

REFLECTION

SCATTERING

REFRACTION

TRANSMISSION

- UV ABSORBED by OZONE IN STRATOSPHERE INFRARED ABSORBED BY

- BY CLOUDS, ICE, SNOW & WATER

- BY AEROSOLS, WATER DROPLETS, ICE CRYSTALS, AIR POLLUTANTS, DUST, POLLEN

LIGHT IS BENT AS IT MOVES THROUGH VARIED DENSITIES

WHEN ENERGY PASSES THROUGH A MEDIUM

CO2&H2O vapor methane, nitrous oxide

1. ABSORPTION

2. REFLECTION

3.SCATTERING

4. REFRACTION

5. TRANSMISSION

Less than ______of the incoming solar radiation is received by the Earth’s surface

half

Surface properties of the Earth and Absorption of Energy:

Color:

Texture:

Reflection vs. Absorption & Radiation

Rough surface absorbs smooth surface reflects

Light (white) reflects dark (black) absorbs

Absorption  Good absorbers are also good re-radiators.

 What type of surface is the best absorber?

 What type of surface is the best reflector of radiation?

– Dark – Rough

– Light – Shiny – Flat

Snow and Ice reflect insolation and remain cold.

Pavement warms before grassy lawns.

ELECTROMAGNETIC SPECTRUM: LAB

Increasing wavelength


visible

10-10 10-8 10-6 10-4 10-2 10 0 10 2 10 4


Infrared Microwaves

Radio waves

Decreasing wavelength

Spectroscope Lab

Greenhouse Effect

Short wavelength visible light enters the greenhouse, is absorbed, then re-radiated as longer wavelength infrared (heat). The glass traps the infrared.

What is Global Warming?

An ___________ in the Earth’s Average surface air temperature

increase

THE GREENHOUSE EFFECT

139

THE GREENHOUSE EFFECT

Energy absorbed

HEAT IS TRAPPED BY

THE GLASS OF THE GREENHOUSE

Incoming is Short wave Ex: Visible light outgoing is

Longer wave Infrared

140

 Short wave radiation like ___________ passes through the glass of a greenhouse and is _______________ by the objects inside the greenhouse.

Visible light

absorbed

141

 These objects __________________ the energy as

____________________, which get reflected back into the greenhouse and warms the air.

infrared Long Wave Radiation

reradiate

142

 In Earth’s atmosphere, there are many gases that act like the glass of a greenhouse and ________ long-wave radiation, keeping it in the Earth’s Atmosphere. These are known as…

trap

143

Greenhouse Gases!

144

Greenhouse Effect  CO2 and H2O absorb infrared that is re-radiated from the surface of the Earth. Therefore, holding that heat in the atmosphere and raising the global temperature.

What are the Greenhouse gases?

CO2 H20 VAPOR

METHANE GAS INFRARED

Ozone

CFCs

Without some greenhouse gases, the Earth would be too _____________ for us to survive. But an overload of greenhouse gases creates a problem as well!

cold

How does too Much contribute to Global warming?

CO2 H20 VAPOR

METHANE GAS

INFRARED

CO2

CO2 absorbs infrared

Greenhouse Effect  What human activities contribute to CO2

production and an increase in the greenhouse effect?

– Burning of fossil fuels – Global deforestation

If present trends continue possible effects may include

 Rising sea levels due to melting polar ice caps;

 Increasing frequency and severity of storms and hurricanes;

 More frequent heat waves and droughts; and

 Relocation of major crop growing areas.

A B c

Which of the following best represents the type of energy received by the Earth and the re-emitted by the Earth?

A B

A)   INSOLATION

C) VISIBLE LIGHT

B) ULTRAVIOLET

WHICH TYPE OF ENERGY IS REPRESENTED BY THE RADIATION AT B?

D) INFRARED ENERGY

An energy resource !that is

________________________________

_______.!

Being used faster than Earth Produces

it!

What is a NON-RENEWABLE RESOURCE?

155

Examples:!__________________ !Fossil Fuels, minerals!


156

To make our non-renewable resources last longer we can

________________________________

_____________.!

Reduce!Reuse!

Recycle!


157

An energy resource !that is

________________________________

_______.!

Earth supplies faster than we use it

“unlimited”!

What is a RENEWABLE RESOURCE?

158

Examples: _______________________________ !Solar, wind, biomass

(trees etc..)!


159

A renewable resource produces less

_________ (substance that can harm living things and/or the

environment!

pollution!


160

Look at the pie graph!!!

 Only 7% of our energy consumption is from renewable resources!!! Try to make little changes in your life to reduce your dependence on Non-Renewable Resources!

 What do you plan to do?

unit 1: energy power point science 8

Documents

stored energy

energy changes

total energy

chemical energy

nuclear energy

greatestkinetic energy

icegains energy

energy transferuids