Chapter 10: Questions Flashcards
In what sense do we say there is no such thing as cold?
An object that is cold only lacks thermal energy.
How is thermal energy transferred from one place to another by convection?
It’s transferred by the movement of fluids.
What happens to the pressure of air as it rises? What happens to its volume? It’s temperature?
As air rises it’s pressure and temperature decreases. It’s volume expands.
Which normally cools faster; a black pot of hot water, or a silver pot of hot water?
A black pot because it’s a good conductor of heat.
Do the molecules in a liquid all have about the same speed or is there a wide variety of speeds?
There is a wide variety of speeds.
Why is perspiration a cooling process?
Faster molecules evaporate allowing heat to escape your body.
What happens to the temperature of a body of water molecules condense upon it?
The temperature increases.
Distinguish between evaporation and boiling.
Evaporation is changing a liquid to a gas without hearing. Boiling is changing a liquid to a gas with heating.
Why does increasing the temperature of a solid make it melt?
The speed of the molecules increase allowing them to break free and change states.
Why does decreasing the temperature of a liquid make it freeze?
The speed of the molecules slow down, changing the state due to the frozen molecules.
Does a liquid release or absorb energy when it evaporates? When it solidifies?
It absorbs energy when it evaporates and releases energy when it solidifies.
Why does blowing over the surface of hot soup cool the soup?
The air you blow on it moves hot air out, allowing evaporation to continue.
Distinguish between a heat conductor and an insulator.
A conductor transfers thermal energy. An insulator blocks the transfer of thermal energy.
