Energy in the Earth A. Types of Energy 1. Kinetic: the working energy of a moving body 2. Potential:...

Post on 29-Dec-2015

214 views 1 download

Tags:

Transcript of Energy in the Earth A. Types of Energy 1. Kinetic: the working energy of a moving body 2. Potential:...

Energy in the Earth

A. Types of Energy

1. Kinetic: the working energy of a moving body

2. Potential: stored energy of a body at restB. Electromagnetic Radiation It is the ultimate source of energy on earth from

the sun. EMR travels as a wave in space at the speed of light

3.00 * 108 m/sec All objects give off electromagnetic energy

1. The Electromagnetic Spectrum

C. When energy comes into contact with a surface several interactions can result.

1. Reflected: EMR waves are bounced back.

2. Refracted: Energy waves are bent.

3 Scattered: Reflection & Refraction.

4 Transmitted:

Energy passes through a material.

5 Absorbed: Energy is taken into a material.

6 Reradiated:

Energy is released

from a material at a longer

wavelength called

infrared heat energy.

D. Energy Transfer

1. Radiation: is the transfer of energy across empty space.2. Conduction: Movement of heat through solids. Involves the collision of molecules.3. Convection: The movement of heat through liquids &

gasses.

Heat is moved by convection cells or currents.

Driven by density differences

Electromagnetic Energy Transfer in the

atmosphere, hydrosphere and lithosphere.

Infrared energy Reradiated

E. Heat & Temperature1. Temperature: is a measure of kinetic energy Increase Temp Increase KE

2. All matter is made up of particles that are in a state of

continuous, random motion.3. Heat flows from high to low… Sources – High Heat Sinks – Low Heat

4. The unit of heat energy is called the CALORIE.

Specific heat: is the amount energy needed to raise the temperature of 1 gram of a substance 1° Celsius.

1 calorie is needed to raise the temp of 1g of H2O 1˚

Celsius.

Law of Conservation of Energy

Amount lost by a source = Amount gained by Sink

5. Specific Heat Calculations Specific Heat Equation Is Used for increasing the temperature of a substance (kE)

q=mCΔT q= heat m= mass C = Specific Heat

ΔT = Change in Temperature

Specific Heat Equation q=mCΔT

Problem 1:The temperature of a copper was raised from 20˚C to 100 ˚C Its mass was 30 grams. How many heat calories were used to raise the temperature?

Heat Calories =

Problem 2:The temperature of a water was raised from 10˚C to 90˚C Its mass was 50 grams. How many heat calories were used to raise the temperature?

Heat Calories =

Problem 3:The temperature of a ice was raised from -20˚C to -10˚C Its mass was 50 grams. How many heat calories were used to raise the temperature?

Heat Calories =

Substance Mass TempChange ºC

Specific Heat 

Calories Needed

Water 10 g. 50º - 10º    

Basalt 10 g. 50º - 10º    

Iron 10 g. 50º - 10º    

Lead 10 g. 50º - 10º    

Ice 100 g. 40 º - 5 º    

Water 100 g. 3º - 2º    

Granite 50 g. 300º - 250º    

Latent Heat (Hidden Heat) When a substance changes state potential energy is

added to the material with out an increase in temperature.

F. The Latent Heat of Fusion. A Change from a solid to liquid or back

(Melt/Freeze)

1. Ice when heated from 0°C to a melt at 0°C does not show an increase in temperature.

2. Heat is changed to potential energy. Ice molecules store the heat & break the

crystalline solid.

Latent Heat Equations

Latent Heat of Fusion Equation

Used During a Phase Change (pE during freeze or melt)

q=mHf

Problem 1:The temperature of a ice was raised from 0˚C to 0˚C as a liquid Its

mass was 1000 grams.How many heat calories were used to change states?

Heat Calories =

Problem 2:The temperature of a ice was raised from 0˚C to 0˚C as a liquid Its

mass was 69 grams. How many heat calories were used to change states?

Heat Calories =

q= heat C = Specific Heat

m= mass T = Temperature

f = fusion V = vaporization

G. Latent Heat Of Vaporization A changing from a liquid to a gas or

back. 1. Boiling Water @ 100˚C will continue

to gain heat with out an increase in temperature till water molecules break apart into a gas.

When a substance changes a state from Solid to a liquid or liquid to gas It must gain latent heat

• MELTING / FREEZING

When a substance changes a state from Gas to liquid or liquid to a solid It must lose latent heat

•Evaporization / Condensation

Latent Heat of Vaporization Equation Used During a Phase Change (pE during vaporization or condensation)

q=mHV

Problem 1:The temperature of a water was raised from 100˚C to 100˚C as a gas Its mass was 1000 grams. How many heat calories were used to change states?

Heat Calories =

Problem 2:The temperature of a water was raised from 100˚C to 100˚C as a gas Its mass was 69 grams. How many heat calories were used to change states?

Heat Calories =

q= heat C = Specific Heat

m= mass T = Temperature

f = fusion V = vaporization

Latent Heat Equations

Latent Heat

Seasons

A.The Seasons are Caused By

• The earth’s tilt on its axis @ 23.5°.

• The earth’s revolution around the sun.

Winter Solstice

North Pole has 24 Hrs Darkness

Note @ 23.5°S

Tropic of Capricorn

The Sun is Directly Over Head

Summer Solstice

North Pole has 24 Hrs Daylight

Note @ 23.5°N

Tropic of Cancer

The Sun is Directly Over HeadEquinoxes: All portions of the earth receive 12 hrs of daylight & darkness. The sun is directly overhead at the equator.

Note the sun is never directly overhead in New York!

What Season in the Picture Below?

Celestial Dome and the Seasons

1 4

32

 Insolation:Insolation: In Coming Solar Radiation In Coming Solar Radiation

A. Insolation is the electromagnetic energy or radiation received on earth from the sun.

Intensity of Insolation:Intensity of Insolation:

B. Is the rate at which the energy is received.

• As the angle of sun light hitting the earth increases, the intensity of heat absorbed increases.

1. Visible sun light is the most intense energy received on earth that reaches the ground. o Energy can be

ABSORBED or taken into a material and warmed; then released or re-radiate back into the environment as heat.

o Heat Energy is radiated at a longer wavelength called INRARED.

o X-Rays & are absorbed by magnetic field of the earth

o UV Ray’s are absorbed in the ozone layer.

2. Global Warming is the average increase in the earth's temperature.

a. Normally energy gained during the long summer hours is lost in the short winter hours.

Resulting in a radiative balance and the earth remains at a constant average temperature.

3. Greenhouse Effect is a rise in the earths average temperature caused by over heating of trapped sunlight.

Incoming short wave radiation from the sun is absorbed by

greenhouse gasses and converted to heat energy.

- CO2 Carbon Dioxide- CH4 Methane - N20 Nitrous Oxides- H20 Water Vapor

The absorbed radiation is changed to Infrared heat energy at a longer wave length which becomes trapped and the temperature rises.

4. The earth is currently experiencing a increase in its over all average temperature; Which in turn causes changes in climate.

A warmer Earth may lead to changes in rainfall patterns, a rise in sea level, and a wide range of impacts on plants, wildlife, & humans.

C.C. Factors that Determine The Angle of Factors that Determine The Angle of InsolationInsolation

1. 1. Shape of the Earth and Latitude• The angle of insolation changes with a curved

surface @ different latitudes. At the poles The angle of insolation is low…. More light is reflected making it cold..

At the Equator The angle is greater More light is absorbed making it hot.

2. Season of the Year and Latitude

a. The angle of insolation at a specific latitude

changes with each season.

b. Note the Maximum and Minimum Angles of Insolation from

June to December in the diagram.

Direct ray’s strike the earth perpendicular at a 90° angle

~ Only occurs between 23.5°N and 23.5°S through out year.

~ The sun is never directly over head in New York.

1. What happens to the amount of sun light from June to December?

2. What happens to the Altitude of the Sun from June to December?

3. What happens to the temperature of the location from June to Dec.?

4. What will happen to the length of the persons shadow from June

to December?

3. Time of Day3. Time of Day

Angle of Insolation & Intensity Change Angle of Insolation & Intensity Change through out the day.through out the day.

•Low @ sunrise and sunset so it is coolLow @ sunrise and sunset so it is cool

•High @ solar noon so it is hotHigh @ solar noon so it is hot

D.D.Duration of InsolationDuration of Insolation• The number of hours of daylight

received by an area. 1. Atmospheric temperature depends

upon the intensity & duration of sunlight.

a. Daily surface temperatures and insolation

• Maximum Daily Temp 2-3 pm

• Minimum Daily Temp Before Sunrise

• Temperature lag created by surface absorption of heat and subsequent re-radiation of energy at a later time.

Gaining Energy

Losing Energy

b. Yearly surface temperaturesb. Yearly surface temperatures

• Maximum Duration - June 21Maximum Duration - June 21stst (15 +/- (15 +/- hours) Gaining Energyhours) Gaining Energy

• Minimum Duration - December 21Minimum Duration - December 21stst (9+/- (9+/- hours) Losing Energyhours) Losing Energy• Temperature lag created by surface Temperature lag created by surface absorption of heat and subsequent re-absorption of heat and subsequent re-radiation of heat at a later time.radiation of heat at a later time.

c.c. Yearly energy budgets for different Yearly energy budgets for different seasons & latitudesseasons & latitudes

In the Northern HemisphereIn the Northern Hemisphere

• Maximum Insolation - June 21st. Maximum Insolation - June 21st. SurplusSurplus

• Minimum Insolation - December 21st. Minimum Insolation - December 21st. DeficitDeficit

Summery Factors Effecting Summery Factors Effecting InsolationInsolation

• The shape of the Earth

• Latitude

• Season or Time of Year

• Time of Day

Carbon

Neon

Argon

Elements can be identified by the electromagnetic energy they radiate through identification of an emission spectrum.

http://home.achilles.net/~jtalbot/data/elements/

Hydrogen

Helium

Lithium

  

Oxygen

Nitrogen

Sodium

Sulfur