Thermodynamics #1
Methods of Heat Transfer - Conceptual

Helpful Sources: 
https://www.physicsclassroom.com/class/thermalp/u18l1e.cfm 


https://www.youtube.com/watch?v=r3tC-ocdVoQ&t=1s 


Heat Transfer 
Which type of heat transfer occurs in fluids: gases and liquid?




Which type of heat transfer occurs by means of Electromagnetic waves?




Which type of heat transfer occurs in solids?




What is the role of “loose” electrons in heat conductors?




Why does a piece of room-temperature metal feel cooler to the touch than wood or cloth?




A row of dominoes is placed upright, one next to the other. When one is tipped over, it knocks against its neighbor, which does the same in cascade fashion until the whole row collapses. Which of the three types of heat transfer is this most analogous to?




Which will undergo the greater rate of cooling down: a red hot poker in a warm oven, or a red hot poker in a cold room (or do they both cool down at the same rate?) - Hint: think about convection vs. conduction vs. radiation. 




If you stick a metal shovel into a pile of snow. After a couple of minutes, your hands become cold too. Does the cold flow from the snow to your hand?




A cup of coffee may be too hot to drink. If you take off the lid of the coffee cup, how might that make it easier to drink?



Explain the difference between forced convection and natural convection.




What is more likely to heat you up faster, the ultraviolet radiation from the sun or microwaves? (Hint: UV light has a higher frequency than microwaves.)



 
In Montana, the state highway department spreads black coal dust on top of snow. When the sun comes out, the snow rapidly melts. Why?



 
In the summertime, do you want the ceiling fan to push the air down or up?



 
If a material conducts electricity (like silver), it is good at conducting heat too. True or false? Why?



 
Which one will burn your hand faster: A thick spoon or a thin spoon in hot soup?




In the chart below, identify each scenario as:
Insulation, Conduction, Natural Convection, Forced Convection or Radiation.
Process Description
Process Type:
An ice cube melts in your hand.


Your hand gets hot due to shuffling coals with a golden metal poker.


You sit next to the fireplace and are warmed up by its red light.


A bucket of ice-water is dumped on your head at a football game.


Your coat keeps you warm during the winter.


The inside of your car feels like a sauna after sitting in the parking lot for an hour in the middle of summer.


If you are ever in a burning house, the fire department warns against touching the door knobs.


After running the track for 30 minutes, your best friend sits down in the locker room. You can see steam rising from his head.


A piece of aluminum that is attached to a hot circuit to absorb the heat is called a “heat sink”.


The air around the heat sink takes the heat away.


Pipes in your refrigerator carry very cold Freon to cool down the interior.


On a hot day, sweat runs down your face to cool you down.


Santa starts to overheat, because the chimney he’s climbing down has a fire going on.


A pot is directly on the fire.


The soup on the bottom of the pot rises to the top of the pot.


A blow-dryer dries your hair with dry, hot air.


The walls of your house are hollow to keep it cooler in the summer and hotter in the winter.


The ceiling fan in your room makes you feel cooler.


An igloo, even though it itself is cold, keeps you warm in Antarctica.


A person touches a hot light bulb and gets burned!


Pancakes are made on a stove.


To ensure consistency in his stew, a man takes a ladle to stir it around in the hot pot.


A hot-air balloon begins to elevate.