Thermal Energy #1
Cold things have thermal energy. (True or False)
True
Heat transfer occurs only from __________ objects to __________ ones.
Hot to cold!
A material that traps heat/cold in well and conducts heat poorly is called a(n) __________.
What is an insulator?
A system in which matter can escape.
What is an open system?
A system in which matter cannot escape.
This is a name for the average amount of kinetic energy in the particles of a substance
What is thermal energy?
Name three phases of matter in order from least kinetic energy to most kinetic energy.
solid, liquid, gas
Particles in a ________ have lots of space between them.
What is a gas?
Paper is a good _______________ because it reduces heat transfer.
Insulator
A drop of food coloring spread faster in hot water than in cold water. Why?
Particles in hot water move faster.
During_____________, heat is transferred by the movement of currents within a fluid.
What is convection?
During __________ heat is transferred by direct contact with another object.
What is conduction?
During ____________ heat is transferred through electromagnetic waves.
What is Radiation?
The ___________ particles an object has at a given temperature; the more thermal energy it has.
More
If two glasses of water are at the same temperature, the average kinetic energy of the particles of water in each glass is the _______________.
Same
Convection can only happen in a _______ or a ________.
Describe how conductors and insulators differ. Include an example of each.
A material that prevents the flow of energy is called an insulator. A material that permits the flow of energy is called a conductor.
An example of an insulator would be air, wool, plastic, etc.
An example of a conductor would be silver, aluminum, iron, metal
A cup with a lid causes a hot liquid in it to drop in temperature ___________ in a cup without a lid.
Less than.
Particles of water in liquid form go into the air over time. (liquid --->gas)
What is evaporation?
Water vapor changing into a liquid over time.
What is condensation?
A hot metal spoon is placed in a cup of cold water. Which way does energy move?
From the spoon into the water.
Water droplets form on the outside of a glass of ice water. Where does this water come from?
The air around the cup.
A cup of ice water has a lid that seals it completely, so no matter can get in or out. After 30 minutes, the water is warmer. Why?
Energy transferred into the cup system from the warmer surroundings.
An object that is moving has _______ energy.
What is kinetic?
Explain why the water in a filled bathtub may be at the same temperature as water in a teacup, but the water in the bathtub has more thermal energy.
Even though the water in a filled bathtub may be at the same temperature as water in a teacup, the water in the bathtub has more thermal energy because it contains a greater number of water molecules.