Energy Transfer -
High Concentration
To Low Concentration
Conduction -
Transfer of heat from molecule to molecule.
**Most effective in solids
Convection -
-transfer of heat by movement in fluids
**caused by density differences
In atmosphere
In oceans
In lithosphere
Radiation -
Transferred via electromagnetic waves
***requires no medium
Energy Flows from
Hot (Source) to
Cold (Sink)
Conduction Lab
DO NOW:
convection
radiation
conduction
radiation
conduction
conduction
convection
radiation
convection
radiation
conduction
Cond.
radiatio
convection
Temperature -
the temperature of a body is a measure of the average kinetic energy of its particles��
High Temp.=High KE
Low Kinetic Energy
= Low Temperature
Do Now
-8
5
16
27
310
31
336
-20
248
68
Absolute Zero - The temperature at which molecular activity is at a minimum
Units of Heat
A calorie (cal) is the amount of heat required to raise the temperature of 1 gram of of water by 1° C.
1 cal = 4.186 Joules
1 kilocalorie equals 1000 calories.. When you hear that some food has 200 Cal, that means it has the potential of transferring 200 kilocalories of heat energy to the body.
A BTU is defined as the quantity of energy necessary to raise the temperature of 1 lb. of water 1° Fahrenheit.
Approx. 400 Calories
Firewood
Wood �Species
Osage Orange (Hedge)�Hickory, Shagbark�Eastern Hornbeam�Ironwood�Beech, Blue�Birch, Black�Locust, Black�Hickory, Bitternut�Locust, Honey�Apple�Mulberry�Oak, White�Beech, High�Maple, Sugar�Oak, Red�Ash, White�Birch, Yellow�
Your favorite greasy spoon.
Specific Heat
how much heat is required to change the temperature of a unit mass of a substance by 1 degree is called its specific heat.
Water -
Has a high specific heat
Heats up slowly, cools off slowly
Walton Lake
Lead -
Has a low specific heat
Heats up quickly, cools off quickly
Phase Changes-
Gas
melt
vaporization
Cond.
freezing
kinetic
potential
potential
release
same
water
Heat Calculations:
Electromagnetic energy (radiation from the sun) may be :
Surface properties -
Good Absorber = dark and rough
Good reflector = light and smooth
Absorber or reflector?????
Greenhouse Effect
1966 Plymouth Satellite
Ozone
“Ozone Alert”
Ozone in stratosphere – blocks harmful UV radiation.�
Ozone depletion – ozone reacts with CFCs
Extinction of the Dinosaurs
Aerosols- very fine particles that remain suspended in the atmosphere.
EX: Volcanic Ash or Dust
Eruption
as
Aerosols reflect insolation resulting in cooling
Temperature Lag -
Most intense insolation = June 21st
Hottest time of year = late July
Sun is most intense at noon
Hottest time of day is around 3pm
As long as the earth gains more energy than it loses, the temperature will increase