Which object has more energy - a cold one or a hot one?
Thermal Energy- total of potential and kinetic energy that makes up a body of matter.
Energy is the ability to cause changes in matter.
4-21-09
How is potential energy different from kinetic energy?
kinetic energy - energy in motion
potential energy - energy not in motion; greater the distance and mass, the more potential energy
thermal energy - the combination of potential and kinetic energy
- drop of hot water vs. tub of cold water
- drop of hot water = high kinetic energy
- tub of cold water = lots of potential energy
04-22-09
Does cold move to hot or does hot move to cold?
- Hot always moves to cold; High energy moves to low energy
Temp 1 hot =48 Temp 1 Cold = 18
Temp 2 hot = 29 Temp 2 Cold = 21
- Heat is transferred by particles bumping into each other
calorie - amount of heat required to raise one gram of water 1 degree celsius
04-23-09
What is the coldest something can get?
thermometer - measures temperature; liquids in the thermometer expand or contract based on how hot or cold something is.
hotter = more motion
colder = less motion
Absolute Zero - so cold, there is not motion in the particles of an object
Celsius - water freeze at 0 and boils at 100; absolute zero = -273
Fahrenheit - water freezes at 32 and boils at 212
Kelvin - water freezes at 273, boils at 373; absolute zero = 0
04-27-09
How is energy transferred from one object to another?
04-28-09
Does boiling water keep getting hotter once it boils?
Experiment: Heat water to boiling and take the temperature. Continue to apply heat to the water and see if temperature changes.
Law of conservation of energy - energy cannot be created or destroyed - it can only move from one place to the next
04-29-09
Why do you shut the windows in your home when you turn on the AC?
04-30-09
What is the difference between an insulator and a conductor?
05-01-09
Write this down.
1. Picture of cooler
2. Problem, Hyp.
3. Tell about conduction and convection w/examples
4. Tell about the experiment (what we're doing with the ice cube)
5. Tell how you stop convection and conduction in your box
6. Results
7. Conclusion
8. Error
05-05-09
What were some possible errors in our experiment?
f
05-06-09
How does radiation affect people?
radiation - the movement of energy through electromagnetic waves (radio, microwave, infrared, visible light, etc.)
Imagine that you are trying to build a house that is extremely energy efficient. You do not want it to lose heat in the winter and you want to keep the cold air in during the summer. (Think about what you did with your ice box)
Make a pamphlet recommending what home owners could do to stop energy loss via conduction, convection, and radiation (think windows). Give at least 5 examples of what could be done, draw a diagram to illustrate where it would be done, and tell if it is stopping conduction, convection, or radiation.
• 5 points for the examples
• 5 points for correctly identifying if it stops conduction, convection, or radiation
• 5 points for diagrams that show your examples
• 3 points for overall neatness
Example: Make sure all doors are closed at your home. This helps to stop _______________.