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Definitions
Examples
Heat in Nature
Fill in the Blank
Application
100
Define friction.
The resistance caused when two surfaces rub together.
100
Give an example of convection.
Touching a hot pot
100
What direction does a sea breeze travel?
From sea to land.
100
Oceans keep land near them from having temperature extremes. We say that oceans _______________ temperatures.
Moderate
100
A student burns his hand on the hot plate in the lab and then runs it under cold water. What type of transfer occurs here?
Heat transfer - conduction
200
Define Brownian motion.
The jiggling motion of particles, invented by Robert Brown.
200
Give an example of a technology used to keep something cool.
Car engine, fridge.
200
Describe two characteristics of a land breeze.
- mild wind - flows from land to water - usually occur in the evening - carry air pollutants out to sea - weaker than sea breezes (less temperature difference between land and water)
200
The first person to observe a sign of molecular motion was __________ _____________.
Robert Brown
200
You are told to find the temperature of an unknown substance in the lab. Theoretically, how would you determine the temperature mathematically? **NOT using a thermometer.
Add the kinetic energies of all the particles in the unknown substance and divide by the total number of particles.
300
Define heat.
The sum of all kinetic energies of all particles in an object.
300
Provide two examples of how energy can be transferred within an oven.
Conduction - baking pan touching cake. Convection - air circulates to heat pan and oven walls Radiation - oven walls heat up and radiate heat
300
Why do oceans help moderate climates?
They can store large amounts of thermal energy.
300
The average of all the kinetic energies of an object is its ______________.
Temperature
300
Your younger sibling asks how soup heats up when you cook it on the stove. How would you explain the idea that convection heats the soup in the pot?
The soup closest to the burner on the bottom of the pot heats up faster than the soup at the top. Once it becomes warm, it becomes less dense and rises to the top of the pot. The cold soup sinks to the bottom and warms up. It then moves toward the top. The soup continually circulates until the desired temperature.
400
Define radiation.
The transfer of heat by electromagnetic waves.
400
State an example of two items where the temperatures are the same but the heat is different.
A jar of water with the same temperature (thermometer) but one jar has more water so it has more heat.
400
Compare the difference between the climate in Edmonton and the climate in Hawaii based on the trends.
Edmonton has a wide range of temperatures because it is not close to an ocean. Hawaii has little temperature differences because the surrounding ocean stores thermal energy.
400
A process of heat transfer that involves circular flow of air or liquids is called ______________.
Convection
400
You are asked to design a device that will heat up to dangerously high temperatures. However, this device needs to be handled. Suggest three materials that would be safe for humans to handle at these high temperatures.
Wood, rubber, glass.
500
Compare the definitions of convection and conduction.
Convection is the transfer of heat through air or water molecules. Conduction is the transfer of heat through contact.
500
State the two types of energies we talked about and give an example of each.
Thermal energy - heat from the sun, hot stove, match etc. Kinetic energy - particles move faster in a glass of water than your desk.
500
If you lived in a lake-front cottage what time of the day would the cottage be the warmest? What time of the day would the cottage be the coldest? Explain one point for each.
Warmest at night because air of water cools more slowly than air over land. Coolest during the day because cool air from the lake moves toward the land.
500
A jiggling motion of small particles in water is called _______________ ___________.
Brownian motion
500
Part of your job at a chemical plant requires you to mix solutions together. You have to determine which substance dissolves in water the fastest. Describe a factor you could control to have one substance dissolve faster than another.
Temperature - the higher the temperature, the faster the particles move and the faster the substance will dissolve.