Vocabulary
Energy that comes from or relates to movement.
How does energy transfer between molecules?
Energy transfers between molecules when molecules collide with each other.
What happens to molecules of an object when it cools down?
The molecules slow down.
What are the tiny things all things are made of called?
Molecules.
Define thermal energy
Thermal energy is the total kinetic energy of an object.
When does energy transfer stop?
When all the objects in a system are the same temperature.
If something looses energy where does it go? If something gains energy where does it come from?
The energy is transferred because it cannot be created or destroyed.
Define absolute zero
Define temperature
The average kinetic energy of an object.
Two objects of different temperatures come in to contact with each other. Will the cooler object transfer energy to the hotter one, or will the hotter object transfer energy to the colder one?
The hotter object will transfer energy to the cooler object.
Explain how air conditioners make cities hotter.
Air conditioners make cities hotter by removing energy from the air inside the space they are cooling. That energy then is released into the air outside.
Define volume
The total measurement of the outside surface of a three-dimensional object.
Name two things that can impact energy transfer.
1. Insulation.
2. Amount of molecules in the space/object.
3. Surface area
4. Starting temperature of the objects.
You have a cup of hot cocoa with 2000 molecules in it and a temperature of 90*C. Your friend has a cup of hot cocoa with 5000 molecules in it and a temperature of 89*C. You each put an ice cube that is 1*C with 100 molecules in your hot cocoa. Which cocoa will be cooler?
Your cocoa will be cooler.
You and your friend each start the day with a 32oz bottle of water, both you and your friends water is 10*C. You have an Owala, your friend has a Gatorade Squeeze bottle. At the end of the day your water is 15*C, and your friends water is 20*C. Why is your water colder than your friends at the end of the day?
Your friends water bottle is not insulated, and your is so your water bottle keeps water colder.
The point at which two things are equal.
There are two heating systems with the same volume, but one has a greater surface area. Which heating system will work better?
One way to cool a room on a hot day without an air conditioner is to place a fan in the window and have the hot air from outside blow over a large bucket of ice water. Why does this cooling system work?
The hot air from outside transfers energy to the cool water so the air is colder after it blows over the bucket of ice water.
- All molecules are moving at the same speed.
- The molecules of the solid sample will be moving around less than the others.
- The molecules of the gas sample will be moving around more than the others.