Thermo-Test One- Concepts 1

What is the net force acting on a car cruising at a constant velocity of 70 km/h on a level road?

0 N.

What is the net force acting on a car cruising at a constant velocity of 70 km/h on an uphill road?

0 N.

In an informative article in a magazine it is stated that tires lose roughly _____ psi of pressure for every 10°F drop in outside temperature.

1 psi

Consider the falling of a rock off a cliff into seawater and eventually settling at the bottom of the sea. Rank the energy transfers and transformations involved during this process.

1. Potential 2. Kinetic 3. Thermal

In what kind of pot will a given volume of water boil at a higher temperature?

A given volume of water will boil at a higher temperature in a tall and narrow pot since the pressure at the bottom (and thus the corresponding saturation pressure) will be higher.

A perfectly fitting pot and its lid often stick after cooking as a result of the vacuum created inside.

A perfectly fitting pot and its lid often stick after cooking as a result of the vacuum created inside as the temperature, and thus the corresponding saturation pressure inside the pan drops.

A perfectly fitting pot and its lid often stick after cooking, and it becomes very difficult to open the lid when the pot cools down. An easy way of removing the lid is to _____ the food.

An easy way of removing the lid is to reheat the food. When the temperature rises to boiling level, the pressure rises to atmospheric value and thus the lid will come right off.

At _____ point the saturated liquid and the saturated vapor states are identical.

At critical point the saturated liquid and the saturated vapor states are identical.

At _____ point the three phases of a pure substance coexist in equilibrium.

At triple point the three phases of a pure substance coexist in equilibrium.

The ordinary temperature scale in the SI system is _____.

Celsius

Classical thermodynamics is based on the average behavior of large groups of particles.

Classical Thermodynamics is based on experimental observations

A gas in a piston-cylinder device is compressed, and as a result its temperature rises. Is this a heat or work interaction?

Compressing a gas in a piston-cylinder device is a work interaction process.

A vapor that is about to condense is superheated vapor; otherwise it is saturated vapor.

False, a vapor that is about to condense is saturated vapor; otherwise it is superheated vapor.

Absorptivity is the fraction of radiation absorbed by a surface that is incident on the surface.

False, absorptivity is the fraction of radiation incident on a surface that is absorbed by the surface.

Silver has a higher thermal conductivity than diamond, and therefore, silver is a better conductor of heat.

False, diamond has a higher thermal conductivity than silver, and therefore diamond is a better conductor of heat.

Emissivity is the ratio of the radiation emitted by a blackbody to the radiation emitted by a surface at the same temperature.

False, emissivity is the ratio of the radiation emitted by a surface to the radiation emitted by a blackbody at the same temperature.

For an adiabatic process, the net work is zero.

False, for an adiabatic process the net work is not necessarily zero. Gas expansion is an example where adiabatic processes can occur and need work. Work is not always zero in adiabatic processes.

Hydrogen is not a fuel, since it cannot be burned, but it is an energy source, since there are numerous hydrogen reserves in the world.

False, hydrogen is a fuel, since it can be burned, but it is not an energy source, since there are no hydrogen reserves in the world.

Hydrogen is directly obtained from water, and then it is used as a fuel to power cars or generators.

False, hydrogen is obtained from water by using another energy source, such as solar or nuclear energy, and then it is used as a fuel to power cars or generators.

In electric heaters, electrical energy is converted to potential energy.

False, in electric heaters, electrical energy is converted to sensible internal energy.

In the absence of magnetic, electrical, and surface tension effects, the total energy of a system consists of internal energy.

False, in the absence of magnetic, electrical, and surface tension effects, the total energy of a system consists of the kinetic, potential, and internal energies.

Mechanical efficiency is defined as the ratio of indicated thermal efficiency to air standard efficiency.

False, mechanical efficiency is defined as the ratio of the mechanical energy output to the mechanical energy input.

Mechanical energy is the form of energy that can be converted to mechanical work indirectly by a mechanical device such as a propeller.

False, mechanical energy is the form of energy that can be converted to mechanical work completely and directly by a mechanical device such as a propeller.

The combined pump-motor efficiency can be greater than either of the pump or motor efficiency since both pump and motor efficiencies are greater than 1, and the product of two numbers that are greater than one is greater than either of the numbers.

False, the combined pump-motor efficiency cannot be greater than either of the pump or motor efficiency since both pump and motor efficiencies are lesser than 1, and the product of two numbers that are lesser than one is lesser than either of the numbers.

The combined pump-motor efficiency of a pump-motor system is defined as the ratio of the increase in the electrical energy of the fluid to the mechanical power consumption of the motor.

False, the combined pump-motor efficiency of a pump-motor system is defined as the ratio of the increase in the mechanical energy of the fluid to the electrical power consumption of the motor.

The form of energy that crosses the boundary of a closed system because of a temperature difference is work; all other forms are because of heat.

False, the form of energy that crosses the boundary of a closed system because of a temperature difference is heat; all other forms are because of work.

The microscopic forms of energy are those a system possesses as a whole with respect to some outside reference frame.

False, the microscopic forms of energy are those related to the molecular structure of a system and the degree of the molecular activity, and they are independent of any outside reference frame.

On a hot summer day, a student turns the fan on when he leaves his room in the morning. When he returns in the evening, the room will be cooler. Assume all the doors and windows are kept closed.

False, the room is warmer when he returns in the evening. This is because energy is added to the room air in the form of electrical work.

Thermal energy is the sensible and latent forms of chemical energy, and it is referred to as heat in daily life.

False, thermal energy is the sensible and latent forms of internal energy, and it is referred to as heat in daily life.

The ordinary temperature scale in the English system is rankine.

False- Fahreinheit

Extensive properties do not depend on the size (extent) of the system

False- they do.

Intensive properties depend on the size (extent) of the system.

False.

The macroscopic forms of energy are those related to the molecular structure of a system and the degree of the molecular activity, and they are independent of outside reference frames.

False. False, the macroscopic forms of energy are those a system possesses as a whole with respect to some outside reference frame.

The state of the air in the atmosphere can be determined without the value of all its properties.

False. In order to describe the state of the air, we need to know the value of all its properties. Pressure, temperature, and water content (i.e., relative humidity or dew point temperature) are commonly cited by the weather forecasters. But, other properties such as wind speed and chemical compositions (pollen count and smog index, for example) are also important under certain circumstances.

The light-year unit has the dimension of mass.

False. In this unit, the word light refers to the speed of light. The light-year unit is then the product of velocity and time. Hence, this product forms a distance dimension and unit.

One pound-force is the force required to accelerate a mass of 32.174 lbm by 9.807 ft/s

False. Pound-mass is the mass unit in the English system, whereas pound-force is a force unit. One pound-force is the force required to accelerate a mass of 32.174 lbm by 1 ft/s2. In other words, the weight of 1-lbm mass at sea level is 1 lbf.

Consider two identical fans, one at sea level and the other on top of a high mountain, running at identical speeds. The mass flow rates of the two fans will be the same.

False. The density of air at sea level is higher than the density of air on top of a high mountain. Therefore, the mass flow rate of the fan at sea level will be higher.

The pressure relative to the atmospheric pressure is called the absolute pressure.

False. The pressure relative to the atmospheric pressure is called the gage pressure.

The pressure relative to an absolute vacuum is called gage pressure.

False. This is the absolute pressure.

Choose the forms in which energy can cross the boundaries of a closed system.

Heat and work

Hydrogen is an _____.

Hydrogen is an energy carrier rather than an energy source.

The specific weight of a system is defined as the weight per unit volume (note that this definition violates the normal specific property-naming convention). Is the specific weight an extensive or an intensive property?

Intensive property

What kind of process does the atmospheric air undergo from a cool morning to a warm afternoon, assuming that the air composition and the velocity do not change, and also that no pressure from motion occurs during the day?

Isobaric process.

A room is heated as a result of solar radiation coming in through the windows. Is this a heat or work interaction for the room?

It is a heat interaction since it is due to the temperature difference between the sun's radiation and the room.

How can you verify if a road is pitched uphill or downhill?

Level meter

A bicyclist picks up speed on a downhill road even when he is not pedaling. Does this violate the conservation of energy principle?

No

An office worker claims that a cup of cold coffee on his table warmed up to 80°C by picking up energy from the surrounding air, which is at 25°C. Is there any truth to his claim?

No

One of the most amusing things a person can experience is when a car in neutral appears to go uphill when its brakes are released. Can this really happen? Note that the car is an isolated system with no external force acting on it.

No

Does the reference point selected for the properties of a substance have any effect on thermodynamic analysis?

No, because in the thermodynamic analysis we deal with the changes in the properties, and the changes are independent of the selected reference state.

Does any of the energy of the sun reach the earth by conduction or convection?

No, it is purely by radiation.

Does quality have any meaning in the superheated vapor region?

No, quality does not have any meaning in the superheated vapor region.

Someone claims that the absolute pressure in a liquid of constant density doubles when the depth is doubled. Do you agree?

No, the absolute pressure in a liquid of constant density does not double when the depth is doubled. It is the gage pressure that doubles when the depth is doubled.

A car is accelerated from rest to 85 km/h in 10 s. Would the energy transferred to the car be different if it were accelerated to the same speed in 5 s?

No, the work done (i.e., energy transferred to the car) is the same, but the power is different.

Consider two closed systems A and B. System A contains 3000 kJ of thermal energy at 20°C, whereas system B contains 200 kJ of thermal energy at 50°C. Now the systems are brought into contact with each other. Will the heat transfer occur from system A to system B?

No. Heat transfers from warmer to cooler objects. So heat will transfer from B to A.

Does propane gas pose a greater risk of fire than methane?

Propane (molar mass = 44.1 kg/kmol) poses a greater fire danger than methane (molar mass = 16 kg/kmol) since propane is heavier than air (molar mass = 29 kg/kmol), and it will settle near the floor. Methane, on the other hand, is lighter than air, and thus it will rise and leak out.

_____ is the ratio of the mass of vapor to the total mass of the mixture.

Quality is the ratio of the mass of vapor to the total mass of the mixture.

An office worker claims that a cup of cold coffee on his table warmed up to 80°C by picking up energy from the surrounding air, which is at 25°C. Which thermodynamic law does this process violate?

Second Law of Thermodynamics

Choose the various effects in a system that produce sensible internal energy.

Sensible internal energy is due to translational, rotational, and vibrational effects.

Statistical thermodynamics is based on the average behavior of large groups of particles

Statistical thermodynamics is based on the average behavior of large groups of particles.

A health magazine reported that physicians measured 100 adults' blood pressure. Regardless of whether the patient is standing, sitting, or lying down, will the blood pressure of the patient be higher when his or her arms are parallel to the body than that when the arms are perpendicular to the body?

The blood vessels are more restricted when the arm is parallel to the body than when the arm is perpendicular to the body. For a constant volume of blood to be discharged by the heart, the blood pressure must increase to overcome the increased resistance to flow.

Which of the following equations can be obtained from hfg, hf, and hg?

The correct equation is hfg = hg − hf.

A househusband is cooking beef stew for his family in a pan. For which of the following options will the cooking time be the shortest?

The correct option is when the pan is covered with a heavy lid. Heavier the lid, the greater the pressure in the pan, and thus greater the cooking temperature.

Choose the forms of mechanical energy of a fluid stream.

The forms of mechanical energy of a fluid stream are kinetic, potential, and flow energies.

Choose the forms of energy that contribute to the internal energy of a system.

The internal energy of a system is made up of sensible, latent, chemical, and nuclear energies

It is well known that warm air in a cooler environment rises. Now consider a warm mixture of air and gasoline on top of an open gasoline can. Do you think this gas mixture will rise in a cooler environment?

The molar mass of gasoline (C8H18) is 114 kg/kmol, which is much larger than the molar mass of air that is 29 kg/kmol. Therefore, the gasoline vapor will settle down instead of rising even if it is at a much higher temperature than the surrounding air. As a result, the warm mixture of air and gasoline on top of an open gasoline will most likely settle down instead of rising in a cooler environment.

If the pressure of a substance is increased during a boiling process, the temperature decreases.

This is false. If the pressure of a substance is increased during a boiling process, the temperature increases since the boiling or saturation temperature of a pure substance depends on the pressure.

At supercritical pressures, there is no distinct phase change process, whereas, at subcritical pressures, there is always a distinct surface between the phases.

This is true. At supercritical pressures, there is no distinct phase change process, whereas, at subcritical pressures, there is always a distinct surface between the phases.

In the absence of compressed liquid tables, the compressed liquid can be approximated as a saturated liquid at a given temperature.

This is true. In the absence of compressed liquid tables, the compressed liquid can be approximated as a saturated liquid at a given temperature

The term hfg represents the amount of energy needed to vaporize a unit mass of saturated liquid at a specified temperature or pressure.

This is true. The term hfg represents the amount of energy needed to vaporize a unit mass of saturated liquid at a specified temperature or pressure.

In the van der Waals equation of state, the constants are determined from the requirement that the critical isotherm has an inflection point at the critical point.

True

Mass m is simply the amount of matter; molar mass M is the mass of one mole in grams or the mass of one kilomoles in kilograms.

True

Completely vaporizing 1 kg of saturated liquid water at 1 atm pressure requires more energy than completely vaporizing 1 kg of saturated liquid water at 8 atm pressure.

True, Completely vaporizing 1 kg of saturated liquid water at 1 atm pressure requires more energy since the higher the pressure, the lower the hfg.

A blackbody is an idealized body that emits the maximum amount of radiation at a given temperature and absorbs all the radiation incident on it.

True, a blackbody is an idealized body that emits the maximum amount of radiation at a given temperature and absorbs all the radiation incident on it.

A gas can be treated as an ideal gas when it is at a high temperature or low pressure relative to its critical temperature and pressure.

True, a gas can be treated as an ideal gas when it is at a high temperature or low pressure relative to its critical temperature and pressure.

A liquid that is about to vaporize is saturated liquid; otherwise it is compressed liquid.

True, a liquid that is about to vaporize is saturated liquid; otherwise it is compressed liquid.

A mechanical efficiency of 100% for a hydraulic turbine means that the entire mechanical energy of the fluid is converted to mechanical (shaft) work.

True, a mechanical efficiency of 100% for a hydraulic turbine means that the entire mechanical energy of the fluid is converted to mechanical (shaft) work.

A system that does not exchange any heat with its surroundings is an adiabatic system.

True, a system that does not exchange any heat with its surroundings is an adiabatic system.

Acid rain causes many lakes and rivers in industrial areas to become too acidic for fish to grow. Also, forests in those areas experience a slow death due to absorbing the acids through their leaves, needles, and roots. Even marble structures deteriorate due to acid rain.

True, acid rain causes many lakes and rivers in industrial areas to become too acidic for fish to grow. Also, forests in those areas experience a slow death due to absorbing the acids through their leaves, needles, and roots. Even marble structures deteriorate due to acid rain.

Acid rain is called so since acids formed usually dissolve in the suspended water droplets in clouds or fog and it comes down with rain droplets.

True, acid rain is called so since acids formed usually dissolve in the suspended water droplets in clouds or fog and it comes down with rain droplets.

An adiabatic process is a process during which there is no heat transfer.

True, an adiabatic process is a process during which there is no heat transfer.

At low levels, carbon monoxide decreases the amount of oxygen supplied to the brain and other organs and muscles, slows body reactions and reflexes, and impairs judgment. At high levels, it can be fatal, as evidenced by numerous deaths caused by cars that are warmed up in closed garages or by exhaust gases leaking into the cars.

True, at low levels, carbon monoxide decreases the amount of oxygen supplied to the brain and other organs and muscles, slows body reactions and reflexes, and impairs judgment. Also, at high levels, it can be fatal, as evidenced by numerous deaths caused by cars that are warmed up in closed garages or by exhaust gases leaking into the cars.

Carbon monoxide is a colorless, odorless, poisonous gas that deprives the body's organs from getting enough oxygen by binding with the red blood cells that would otherwise carry oxygen.

True, carbon monoxide is a colorless, odorless, poisonous gas that deprives the body's organs from getting enough oxygen by binding with the red blood cells that would otherwise carry oxygen.

Common engineering energy conversion techniques pollute the soil, the water, and the air, and environmental pollution is a serious threat to vegetation, wild life, and human health.

True, common engineering energy conversion techniques pollutes the soil, the water, and the air, and environmental pollution is a serious threat to vegetation, wild life, and human health.

Compressibility factor Z represents the deviation from ideal-gas behavior.

True, compressibility factor Z represents the deviation from ideal-gas behavior.

Energy can be transferred to or from a control volume as heat, various forms of work, and by mass transport.

True, energy can be transferred to or from a control volume as heat, various forms of work, and by mass transport.

Global warming is caused because of the excessive amounts of gases such as carbon dioxide, methane, and nitrogen oxide that disturb the delicate balance by trapping too much energy, thereby causing the average temperature of the earth to rise and the climate at some localities to change.

True, global warming is caused because of the excessive amounts of gases such as carbon dioxide, methane, and nitrogen oxide that disturb the delicate balance by trapping too much energy, thereby causing the average temperature of the earth to rise and the climate at some localities to change.

Ground-level ozone is formed when hydrocarbons and nitrogen oxides react in the presence of sunlight in hot calm days.

True, ground-level ozone is formed when hydrocarbons and nitrogen oxides react in the presence of sunlight in hot calm days.

In forced convection, the fluid is forced to move by external means such as a fan, a pump, or the wind.

True, in forced convection, the fluid is forced to move by external means such as a fan, a pump, or the wind.

Mechanical energy can be converted to mechanical work completely and directly, whereas thermal energy cannot be converted to work directly and completely.

True, mechanical energy can be converted to mechanical work completely and directly, whereas thermal energy cannot be converted to work directly and completely.

Ozone irritates eyes and damages the air sacs in the lungs where oxygen and carbon dioxide are exchanged, causing eventual hardening of this soft and spongy tissue. It also causes shortness of breath, wheezing, fatigue, headaches, and nausea and respiratory problems such as asthma.

True, ozone irritates eyes and damages the air sacs in the lungs where oxygen and carbon dioxide are exchanged, causing eventual hardening of this soft and spongy tissue. It also causes shortness of breath, wheezing, fatigue, headaches, and nausea and respiratory problems such as asthma.

Real bodies emit and absorb less radiation than a blackbody at the same temperature.

True, real bodies emit and absorb less radiation than a blackbody at the same temperature.

Smog is made up mostly of ground-level ozone (O3), but it also contains numerous other chemicals, including carbon monoxide (CO), particulate matter such as soot and dust, volatile organic compounds (VOC) such as benzene, butane, and other hydrocarbons.

True, smog is made up mostly of ground-level ozone (O3), but it also contains numerous other chemicals, including carbon monoxide (CO), particulate matter such as soot and dust, and volatile organic compounds (VOC) such as benzene, butane, and other hydrocarbons.

Smog is the brown haze that builds up in a large stagnant air mass and hangs over populated areas on calm hot summer days.

True, smog is the brown haze that builds up in a large stagnant air mass and hangs over populated areas on calm hot summer days.

The Kirchhoff's law of radiation states that the emissivity and the absorptivity of a surface are equal at the same temperature and wavelength.

True, the Kirchhoff's law of radiation states that the emissivity and the absorptivity of a surface are equal at the same temperature and wavelength.

The caloric theory is based on the assumption that heat is a fluid-like substance called the "caloric," which is a massless, odorless, and colorless substance.

True, the caloric theory is based on the assumption that heat is a fluid-like substance called the "caloric," which is a massless, odorless, and colorless substance.

The caloric theory was abandoned in the middle of the nineteenth century after it was shown that there is no such thing as the caloric.

True, the caloric theory was abandoned in the middle of the nineteenth century after it was shown that there is no such thing as the caloric.

The combined pump-motor efficiency cannot be greater than either of the pump efficiency or the motor efficiency.

True, the combined pump-motor efficiency cannot be greater than either of the pump efficiency or the motor efficiency. This is because ηpump-motor = ηpump × ηmotor, and both ηpump and ηmotor are less than one, and a number gets smaller when multiplied by a number smaller than one.

The fluid motion in natural convection is due to buoyancy effect.

True, the fluid motion in natural convection is due to buoyancy effect.

The greenhouse effect can be reduced by reducing the net production of CO2 by consuming less energy (for example, by buying energy-efficient cars and appliances) and planting trees.

True, the greenhouse effect can be reduced by reducing the net production of CO2 by consuming less energy (for example, by buying energy-efficient cars and appliances) and planting trees.

The greenhouse effect is caused by carbon dioxide (CO2), water vapor, and trace amounts of some other gases such as methane and nitrogen oxides that act like a blanket and keep the earth warm at night by blocking the heat radiated from the earth.

True, the greenhouse effect is caused by carbon dioxide (CO2), water vapor, and trace amounts of some other gases such as methane and nitrogen oxides that act like a blanket and keep the earth warm at night by blocking the heat radiated from the earth.

The primary chemicals that pollute the air are hydrocarbons (HC, also referred to as volatile organic compounds, VOC), nitrogen oxides (NOx), and carbon monoxide (CO).

True, the primary chemicals that pollute the air are hydrocarbons (HC, also referred to as volatile organic compounds, VOC), nitrogen oxides (NOx), and carbon monoxide (CO).

The primary source of the pollutants such as hydrocarbons (HC, also referred to as volatile organic compounds, VOC), nitrogen oxides (NOx), and carbon monoxide (CO) is motor vehicles.

True, the primary source of the pollutants such as hydrocarbons (HC, also referred to as volatile organic compounds, VOC), nitrogen oxides (NOx), and carbon monoxide (CO) is motor vehicles.

The sum of all forms of energy a system possesses is called total energy.

True, the sum of all forms of energy a system possesses is called total energy.

The three mechanisms of heat transfer are conduction, convection, and radiation.

True, the three mechanisms of heat transfer are conduction, convection, and radiation.

Fossil fuels include small amounts of sulfur. The sulfur in the fuel reacts with oxygen to form sulfur dioxide (SO2), which is an air pollutant. The sulfur oxides and nitric oxides react with water vapor and other chemicals high in the atmosphere in the presence of sunlight to form sulfuric and nitric acids. The acids formed usually dissolve in the suspended water droplets in clouds or fog. These acid-laden droplets are washed from the air on to the soil by rain or snow. This is known as acid rain.

True, this is known as acid rain.

The absolute temperature scale in the English system is rankine.

True.

The number of moles of a substance contained in a system is an extensive property.

True.

Consider two identical fans, one at sea level and the other on top of a high mountain, running at identical speeds. The volume flow rates of the two fans will be the same.

True. The density of air at sea level is higher than the density of air on top of a high mountain. Therefore, the volume flow rates of the two fans will be the same.

Specific gravity is defined as the ratio of the density of a substance to the density of some standard substance at a specified temperature.

True. The specific gravity, or relative density, is defined as the ratio of the density of a substance to the density of some standard substance at a specified temperature (usually water at 4°C, for which ρH2O = 1000 kg/m3). That is, SG = ρ/ρH2O.

When compressibility factor is further away from _____, the more the gas deviates from ideal gas behavior.

When compressibility factor is further away from 1, the more the gas deviates from ideal gas behavior.

Does a bicyclist pick up speed on a downhill road even when he is not pedaling?

Yes

Consider an automobile traveling at a constant speed along a road. Heat is being added to the atmospheric air by the hotter components of the car. Work is being done on the air as it passes over and through the car.

Yes, heat is being added to the atmospheric air by the hotter components of the car. Work is being done on the air as it passes over and through the car.

Is iced water a pure substance?

Yes, iced water is a pure substance because it has the same chemical composition throughout.

Does hfg change with pressure?

Yes, it decreases with increasing pressure and becomes zero at the critical pressure.

Is it true that water boils at higher temperature at higher pressure?

Yes, it is true that water boils at higher temperature at higher pressure. The saturation temperature of a pure substance depends on pressure. The higher the pressure, the higher the saturation or boiling temperature.

Consider an automobile traveling at a constant speed along a road. The car's radiator transfers heat from the hot engine cooling fluid to the cooler air. No work interaction occurs in the radiator.

Yes, the car's radiator transfers heat from the hot engine cooling fluid to the cooler air. No work interaction occurs in the radiator.

A propane tank is filled with a mixture of liquid and vapor propane. Can the contents of this tank be considered a pure substance?

Yes, the contents of this tank can be considered a pure substance since the chemical composition throughout the tank remains the same.

Is it true that it takes more energy to vaporize 1 kg of saturated liquid water at 100°C than it would at 120°C?

Yes, the higher the temperature the lower the hfg value.

Consider an automobile traveling at a constant speed along a road. The hot engine transfers heat to cooling fluid and ambient air while delivering work to the transmission.

Yes, the hot engine transfers heat to cooling fluid and ambient air while delivering work to the transmission.

Consider an automobile traveling at a constant speed along a road. The warm tires transfer heat to the cooler air and to some degree to the cooler road while no work is produced. No work is produced since there is no motion of the forces acting at the interface between the tire and road.

Yes, the warm tires transfer heat to the cooler air and to some degree to the cooler road while no work is produced. No work is produced since there is no motion of the forces acting at the interface between the tire and road.

Consider an automobile traveling at a constant speed along a road. There is minor amount of heat transfer between the tires and road. Presuming that the tires are hotter than the road, the heat transfer is from the tires to the road. There is no work exchange associated with the road since it cannot move.

Yes, there is minor amount of heat transfer between the tires and road. Presuming that the tires are hotter than the road, the heat transfer is from the tires to the road. There is no work exchange associated with the road since it cannot move.

A room is heated by an iron that is left plugged in. Is this work interaction? Take the entire room, including the iron, as the system.

Yes, this is work interaction since the electrons are crossing the system boundary, thus doing electrical work.

Is state of the air in an isolated room completely specified by temperature and pressure?

Yes- because temperature and pressure are two independent properties.

Can the volume that contains the air-fuel mixture within the piston-cylinder device be used as a system to determine the rate at which an automobile adds carbon dioxide to the atmosphere?

Yes. Carbon dioxide is generated by the combustion of fuel in the engine. Any system selected for this analysis must include fuel and air while it is undergoing combustion. The volume that contains the air-fuel mixture within the piston-cylinder device can be used for this purpose. One can also place the entire engine in a control boundary and trace the system-surroundings interactions to determine the rate at which the engine generated carbon dioxide.

Does the amount of heat absorbed as 1 kg of saturated liquid water boils at 100°C have to be equal to the amount of heat released as 1 kg of saturated water vapor condenses at 100°C?

Yes. Otherwise we can create energy by alternately vaporizing and condensing a substance.

A large fraction of the thermal energy generated in the engine of a car is rejected to the air by the radiator through the circulating water. Should the radiator be analyzed as an open system?

Yes. The radiator should be analyzed as an open system since mass is crossing the boundaries of the system

When you define a system to determine the temperature rise created in a lake when a portion of its water is used to cool a nearby electrical power plant, should we account for all the forms of water entering and leaving the volume selected?

Yes. When analyzing the control volume selected, we must account for all the forms of water entering and leaving the control volume. This includes all streams entering or leaving the lake, any rain falling on the lake, any water evaporated to the air above the lake, any seepage to the underground earth, and any springs that may be feeding water to the lake.

A can of soft drink at room temperature is put into a refrigerator so that it will cool. The can of soft drink should be analyzed as a(n) _____ system.

closed

In the van der Waals equation of state, the constant a represents the increase in _____ as a result of intermolecular forces.

err

A process during which the pressure remains constant is called a(n) _____ process.

isobaric

A process during which the volume remains constant is called a(n) _____ process.

isochoric

A process during which the temperature remains constant is called a(n) _____ process.

isothermal

The absolute temperature scale in the SI system is _____.

kelvin (K)

What is the relationship between m and M?

m = NM where N is the number of moles.

In the van der Waals equation of state, the constant b represents the _____ occupied by the molecules.

volume

Choose the appropriate formula for calculating the density of a substance.

ρ=SG×ρH2Oρ=SG×ρH2O