Objective 1: Temperature, Thermal Energy and Heat
1. What are the three common temperature scales? Fahrenheit, Celsius, and Kelvin.
2. How is the thermal energy related to temperature and heat? Temperature is the measure of the average motion of particles in a substance. Thermal energy is all the energy within the substance of that object. Heat is the transfer of thermal energy.
3. What does having a high specific heat mean? Heat is energy transfered from one thing to another. If it has a high specific temperature, it means the the first object passing heat to the other has a great thermal contact. This is basically the passing of heat from one object to another.
4. Why does an ice cube melt in your hand? The thermal energy in your hand passes the heat from your hand to the ice cube. Since the ice is cold, the heat melts it.
5. Why do some materials get hot more quickly than others? They have more thermal energy.
2. How is the thermal energy related to temperature and heat? Temperature is the measure of the average motion of particles in a substance. Thermal energy is all the energy within the substance of that object. Heat is the transfer of thermal energy.
3. What does having a high specific heat mean? Heat is energy transfered from one thing to another. If it has a high specific temperature, it means the the first object passing heat to the other has a great thermal contact. This is basically the passing of heat from one object to another.
4. Why does an ice cube melt in your hand? The thermal energy in your hand passes the heat from your hand to the ice cube. Since the ice is cold, the heat melts it.
5. Why do some materials get hot more quickly than others? They have more thermal energy.
Objective 2: Scales
1. How do thermometers measure temperature? When the heat increases, the liquid inside the thermometer gets bigger, or expands. When the heat decreases, it shrinks back down.
2. WHow are the three temperature scales alike? How are they different? They are the same because they all measure temperature. They all have a typical freezing point and a boiling point. Fahrenheit's freezing point is 32oF; the boiling is 212oF. Celsius's: 0oC; 100oC. Kelvin: 273.15oK; 373.15oK.
3. Convert 5.0 C to Fahrenheit. 5 * 1.8 = 9 + 32 = 41oF
4. The surface temperature on the planet Venus can reach 860 F. Convert this temperature to degrees Celsius. 860 - 32 = 828 / 1.8 = 460oC
5. How much heat is required to raise the temperature of 5 kg’s of water by 10 K? 5 * 4080 * 10 = 204000J
2. WHow are the three temperature scales alike? How are they different? They are the same because they all measure temperature. They all have a typical freezing point and a boiling point. Fahrenheit's freezing point is 32oF; the boiling is 212oF. Celsius's: 0oC; 100oC. Kelvin: 273.15oK; 373.15oK.
3. Convert 5.0 C to Fahrenheit. 5 * 1.8 = 9 + 32 = 41oF
4. The surface temperature on the planet Venus can reach 860 F. Convert this temperature to degrees Celsius. 860 - 32 = 828 / 1.8 = 460oC
5. How much heat is required to raise the temperature of 5 kg’s of water by 10 K? 5 * 4080 * 10 = 204000J
Objective 3: The Transfer of Heat
1. What are the three forms of heat transfer? Conduction, Convection, Radiation.
2. In what direction does heat move? Up
3. How are conductors and insulators different? Conductors transfer thermal energy well, while insulators do not. Conductors are things like stainless steel and silver; Insulators are things like wood, wool, straw, paper, and air.
4. Would a copper pipe work better as a conductor or insulator? Why do you think so? Conductor because thermal energy would be able to pass through it easily.
5. Suppose you are camping on a mountain, and the air temperature is very cold. How would you keep warm? Would you build a fire or set up a tent? Write an explanation for each action you would take. Tell whether conduction, convection or radiation is involved with each heat transfer. I personally would build a fire and set up a tent, not either/or. However using insulators such as wool to keep you warm are good, because it can trap the heat. This is ... convection?
2. In what direction does heat move? Up
3. How are conductors and insulators different? Conductors transfer thermal energy well, while insulators do not. Conductors are things like stainless steel and silver; Insulators are things like wood, wool, straw, paper, and air.
4. Would a copper pipe work better as a conductor or insulator? Why do you think so? Conductor because thermal energy would be able to pass through it easily.
5. Suppose you are camping on a mountain, and the air temperature is very cold. How would you keep warm? Would you build a fire or set up a tent? Write an explanation for each action you would take. Tell whether conduction, convection or radiation is involved with each heat transfer. I personally would build a fire and set up a tent, not either/or. However using insulators such as wool to keep you warm are good, because it can trap the heat. This is ... convection?
Objective 4: Thermal Energy and Matter
1. What causes matter to change state? The movement of the atoms.
2. What happens to a substance as thermal energy increases? It heats up.
3. Why does the temperature of matter remain the same while the matter changes state? Because the temperature rises, but anything else, such as the matter, is determined on its chemical makeup?
4. What causes a solid to melt? When the object obtains heat, the temperature of that object rises.
5. Why should you poke holes in a potato before baking it? Because a potato is mostly all water, so you have to let it out or it will overheat and burn. Also, so the heat can get inside the potato potato.
2. What happens to a substance as thermal energy increases? It heats up.
3. Why does the temperature of matter remain the same while the matter changes state? Because the temperature rises, but anything else, such as the matter, is determined on its chemical makeup?
4. What causes a solid to melt? When the object obtains heat, the temperature of that object rises.
5. Why should you poke holes in a potato before baking it? Because a potato is mostly all water, so you have to let it out or it will overheat and burn. Also, so the heat can get inside the potato potato.
Objective 5: Using Heat
1. How do heat engines use thermal energy? A heat engine performs the conversion of heat energy to mechanical work by exploiting the temperature gradient between a hot "source" and a cold "sink". Heat is transferred from the source, through the "working body" of the engine, to the sink, and in this process some of the heat is converted into work by exploiting the properties of a working substance (usually a gas or liquid). http://en.wikipedia.org/wiki/Heat_engine
2. How are internal combustion engines different from external combustion engines? How are they similar? They're both engines........... An internal combustion engine has an expanding high-temperature, which means it obtains heat. An external combustion engine is a substance (i.e. air and water) which is boiled in a boiler.
3. Why do you think modern cars use internal rather than external combustion engines? Because it is direct, instead of a sort-of two step process, which would allow the car to go faster. It takes in the heat, expands, and zoom. The other one would have to be heated up separately.
4. What changes of state occur in the refrigerant of a refrigerator? When you open the door, heat goes into the coldness, warming it up somewhat. NEVER the cold goes out; your argument is invalid.
5. If the compressor in a refrigerator stopped working, how would its failure affect the heat transfer cycle? FAIL. This question distracts me. There would be nothing to generate its cycle, so a bunch of heat would come in and all the food/milk/etc would go nasty.
2. How are internal combustion engines different from external combustion engines? How are they similar? They're both engines........... An internal combustion engine has an expanding high-temperature, which means it obtains heat. An external combustion engine is a substance (i.e. air and water) which is boiled in a boiler.
3. Why do you think modern cars use internal rather than external combustion engines? Because it is direct, instead of a sort-of two step process, which would allow the car to go faster. It takes in the heat, expands, and zoom. The other one would have to be heated up separately.
4. What changes of state occur in the refrigerant of a refrigerator? When you open the door, heat goes into the coldness, warming it up somewhat. NEVER the cold goes out; your argument is invalid.
5. If the compressor in a refrigerator stopped working, how would its failure affect the heat transfer cycle? FAIL. This question distracts me. There would be nothing to generate its cycle, so a bunch of heat would come in and all the food/milk/etc would go nasty.
Objective 6: In Hot Water Lab
Goal: Build a containter for a 355 mL aluminum can that keeps water hot.
Your container must:
- minimize the loss of thermal energy from the hot water
- be built from materials approved by Mr H
- have insulation no thicker than 3 cm.
- not use electricity or heating chemicals (hand warmers, etc)
- minimize the loss of thermal energy from the hot water
- be built from materials approved by Mr H
- have insulation no thicker than 3 cm.
- not use electricity or heating chemicals (hand warmers, etc)
With a group of classmates or yourself, brainstorm different materials that prevent heat loss. Write a plan for how you will test these materials. Include a list of things you will test when doing your tests. Test out your ideas to determine the best insulating materials. Keep a log of your results in your lab notebook. Then bring the device to class!
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