Question 1

In an isothermal process

Accepted Answer

A) the volume remains constant. 
B) the temperature remains constant. 
C) no heat is transferred between a system and its surroundings. 
D) the pressure remains constant. 
E) the internal energy is not constant. 
A) the volume remains constant. 
B) the temperature remains constant. 
C) no heat is transferred between a system and its surroundings. 
D) the pressure remains constant. 
E) the internal energy is not constant.

Question 2

In which process will the internal energy of the system NOT change?

Accepted Answer

A) An adiabatic expansion of an ideal gas. 
B) An isothermal compression of an ideal gas. 
C) An isobaric expansion of an ideal gas. 
D) The freezing of a quantity of liquid at its melting point. 
E) The evaporation of a quantity of a liquid at its boiling point. 
A) An adiabatic expansion of an ideal gas. 
B) An isothermal compression of an ideal gas. 
C) An isobaric expansion of an ideal gas. 
D) The freezing of a quantity of liquid at its melting point. 
E) The evaporation of a quantity of a liquid at its boiling point.

Question 3

A 5-gallon container of water (approximately 20 kg)having a temperature of 212°F is added to a 50-gallon tub (approximately 200 kg)of water having a temperature of 50°F.What is the final equilibrium temperature (in °C)of the mixture?

Accepted Answer

A) 54 
B) 36 
C) 18 
D) 66 
E) 14 
A) 54 
B) 36 
C) 18 
D) 66 
E) 14

Question 4

The R value of fiberglass batting,3.5 inches thick,is 11 ft2⋅°F⋅h/BTU.What is the thermal conductivity (in BTU/ft⋅°F⋅s)?

Accepted Answer

A) 7.4 × 10−6 
B) 2.7 × 10−2 
C) 8.9 × 10−5 
D) 1.4 × 10−4 
E) 3.6 × 10−3 
A) 7.4 × 10−6 
B) 2.7 × 10−2 
C) 8.9 × 10−5 
D) 1.4 × 10−4 
E) 3.6 × 10−3

Question 5

In an adiabatic free expansion

Accepted Answer

A) no heat is transferred between a system and its surroundings. 
B) the pressure remains constant. 
C) the temperature remains constant. 
D) the volume remains constant. 
E) the process is reversible. 
A) no heat is transferred between a system and its surroundings. 
B) the pressure remains constant. 
C) the temperature remains constant. 
D) the volume remains constant. 
E) the process is reversible.

Question 6

Determine the heat capacity (in calories/°C)of a lake containing one million gallons (approximately 4 million kilograms)of water at 15°C.

Accepted Answer

A) 4 × 106 
B) 4 × 109 
C) 4 × 103 
D) 1 × 103 
E) 4 × 102 
A) 4 × 106 
B) 4 × 109 
C) 4 × 103 
D) 1 × 103 
E) 4 × 102

Question 7

A 5-g coin is dropped from a 300-m building.If it reaches a terminal velocity of 45 m/s,and the rest of the energy is converted to heating the coin,what is the change in temperature (in °C)of the coin? (The specific heat of copper is 387 J/kg⋅°C. )

Accepted Answer

A) 9 
B) 2 
C) 5 
D) 21 
E) 0.5 
A) 9 
B) 2 
C) 5 
D) 21 
E) 0.5

Question 8

How much heat (in kcal)must be removed to make ice at −10°C from 2 kg of water at 20°C? (The specific heat of ice is 0.50 cal/g⋅°C. )

Accepted Answer

A) 190 
B) 200 
C) 240 
D) 210 
E) 50 
A) 190 
B) 200 
C) 240 
D) 210 
E) 50

Question 9

In an isovolumetric process

Accepted Answer

A) the temperature remains constant. 
B) no heat is transferred between a system and its surroundings. 
C) the pressure remains constant. 
D) the volume remains constant. 
E) the internal energy is constant. 
A) the temperature remains constant. 
B) no heat is transferred between a system and its surroundings. 
C) the pressure remains constant. 
D) the volume remains constant. 
E) the internal energy is constant.

Question 10

An 8 000-kg aluminum flagpole 100-m long is heated by the sun from a temperature of 10°C to 20°C.Find the work done (in J)by the aluminum if the linear expansion coefficient is 24 × 10−6 (°C)−1.(The density of aluminum is 2.7 × 103 kg/m3 and 1 atm = 1.0 × 105 N/m2. )

Accepted Answer

A) 287 
B) 425 
C) 213 
D) 710 
E) 626 
A) 287 
B) 425 
C) 213 
D) 710 
E) 626

Question 11

The R-value of an insulating material is the thickness of the material divided by its thermal conductivity.When an insulating material consists of three layers with R-values R1,R2 and R3,the overall R-value of the insulation is given by

Accepted Answer

A) R = R1 + R2 + R3. 
B)    . 
C)    . 
D)    . 
E)    . 
A) R = R1 + R2 + R3. 
B)    . 
C)    . 
D)    . 
E)    .

Question 12

How much water at 20°C is needed to melt 1 kilogram of solid mercury at its melting point of −39°C? (The heat of fusion of mercury is 2.8 cal/gram).

Accepted Answer

The answer of How much water at 20°C is needed...

Question 13

In braking an automobile,the friction between the brake drums and brake shoes converts the car's kinetic energy into heat.If a 1 500-kg automobile traveling at 30 m/s brakes to a halt,how much does the temperature rise in each of the four 8.0-kg brake drums? (The specific heat of each iron brake drum is 448 J/kg⋅°C).

Accepted Answer

The answer of In braking an automobile,the friction between the...

Question 14

Water at room temperature,20°C,is pumped into a reactor core where it is converted to steam at 200°C.How much heat (in J)is transferred to each kilogram of water in this process? (csteam = 2 010 J/kg⋅°C;Lsteam = 2.26 × 103 J/g;1 cal = 4.186 J. )

Accepted Answer

A) 3.35 × 105 
B) 7.53 × 105 
C) 2.67 × 106 
D) 2.80 × 106 
E) 3.01 × 106 
A) 3.35 × 105 
B) 7.53 × 105 
C) 2.67 × 106 
D) 2.80 × 106 
E) 3.01 × 106

Question 15

A wall is constructed of a 2 inch layer of fiberglass board (R = 8)and six inches of fiberglass batting (R = 19).If the temperature on the outside surface of the fiberglass board is 50°F and the temperature on the inside surface of the fiberglass batting is 68°F,what is the temperature (in °F)at the interface? (The units of R are ft2⋅°F⋅h/BTU. )

Accepted Answer

A) 62 
B) 58 
C) 55 
D) 65 
E) 52 
A) 62 
B) 58 
C) 55 
D) 65 
E) 52

Question 16

Determine the work done by 5 moles of an ideal gas that is kept at 100°C in an expansion from 1 liter to 5 liters.

Accepted Answer

A) 2.5 × 104 J 
B) 1.1 × 104 J 
C) 6.7 × 103 J 
D) 2.9 × 103 J 
E) 8.4 × 103 J 
A) 2.5 × 104 J 
B) 1.1 × 104 J 
C) 6.7 × 103 J 
D) 2.9 × 103 J 
E) 8.4 × 103 J

Question 17

How much heat (in kilocalories)is needed to convert 1.00 kg of ice at 0°C into steam at 100°C?

Accepted Answer

A) 23.9 
B) 79.6 
C) 564 
D) 643 
E) 720 
A) 23.9 
B) 79.6 
C) 564 
D) 643 
E) 720

Question 18

A cup of coffee is enclosed on all sides in an insulated container 1/2 cm thick in the shape of a cube 10 cm on a side.The temperature of the coffee is 95°C,and the temperature of the surroundings is 21°C.Find the rate of heat loss (in J/s)due to conduction if the thermal conductivity of the cup is 2 × 10−4 cal/s⋅cm⋅°C.

Accepted Answer

A) 62 
B) 74 
C) 230 
D) 160 
E) 12 
A) 62 
B) 74 
C) 230 
D) 160 
E) 12

Question 19

Gas in a container increases its pressure from 1 atm to 3 atm while keeping its volume constant.Find the work done (in J)by the gas if the volume is 5 liters.

Accepted Answer

A) 0 
B) 3 
C) 5 
D) 15 
E) 15 × 102 
A) 0 
B) 3 
C) 5 
D) 15 
E) 15 × 102

Question 20

A gas expands from A to B as shown in the graph.Calculate the work (in joules)done by the gas.(1 atm= 1.01 × 105 N/m2. )

Accepted Answer

A) 12 
B) 24 
C) 1.21 × 106 
D) 2.42 × 106 
E) 3.64 × 106 
A) 12 
B) 24 
C) 1.21 × 106 
D) 2.42 × 106 
E) 3.64 × 106

Exam 20: The First Law of Thermodynamics

In an isothermal process

In which process will the internal energy of the system NOT change?

A 5-gallon container of water (approximately 20 kg)having a temperature of 212°F is added to a 50-gallon tub (approximately 200 kg)of water having a temperature of 50°F.What is the final equilibrium temperature (in °C)of the mixture?

The R value of fiberglass batting,3.5 inches thick,is 11 ft2⋅°F⋅h/BTU.What is the thermal conductivity (in BTU/ft⋅°F⋅s)?

In an adiabatic free expansion

Determine the heat capacity (in calories/°C)of a lake containing one million gallons (approximately 4 million kilograms)of water at 15°C.

A 5-g coin is dropped from a 300-m building.If it reaches a terminal velocity of 45 m/s,and the rest of the energy is converted to heating the coin,what is the change in temperature (in °C)of the coin? (The specific heat of copper is 387 J/kg⋅°C. )

How much heat (in kcal)must be removed to make ice at −10°C from 2 kg of water at 20°C? (The specific heat of ice is 0.50 cal/g⋅°C. )

In an isovolumetric process

An 8 000-kg aluminum flagpole 100-m long is heated by the sun from a temperature of 10°C to 20°C.Find the work done (in J)by the aluminum if the linear expansion coefficient is 24 × 10−6 (°C)−1.(The density of aluminum is 2.7 × 103 kg/m3 and 1 atm = 1.0 × 105 N/m2. )

The R-value of an insulating material is the thickness of the material divided by its thermal conductivity.When an insulating material consists of three layers with R-values R1,R2 and R3,the overall R-value of the insulation is given by

How much water at 20°C is needed to melt 1 kilogram of solid mercury at its melting point of −39°C? (The heat of fusion of mercury is 2.8 cal/gram).

Water at room temperature,20°C,is pumped into a reactor core where it is converted to steam at 200°C.How much heat (in J)is transferred to each kilogram of water in this process? (csteam = 2 010 J/kg⋅°C;Lsteam = 2.26 × 103 J/g;1 cal = 4.186 J. )

Determine the work done by 5 moles of an ideal gas that is kept at 100°C in an expansion from 1 liter to 5 liters.

How much heat (in kilocalories)is needed to convert 1.00 kg of ice at 0°C into steam at 100°C?

Gas in a container increases its pressure from 1 atm to 3 atm while keeping its volume constant.Find the work done (in J)by the gas if the volume is 5 liters.

A gas expands from A to B as shown in the graph.Calculate the work (in joules)done by the gas.(1 atm= 1.01 × 105 N/m2. )

Physics and Measurement

Motion in One Dimension

Vectors

Motion in Two Dimensions

The Laws of Motion

Circular Motion and Other Applications of Newtons Laws

Energy of a System

Conservation of Energy

Linear Momentum and Collisions

Rotation of a Rigid Object About a Fixed Axis

Angular Momentum

Static Equilibrium and Elasticity

Universal Gravitation

Fluid Mechanics

Oscillatory Motion

Wave Motion

Sound Waves

Superposition and Standing Waves

Temperature

The Kinetic Theory of Gases

Heat Engines, entropy, and the Second Law of Thermodynamics

Electric Fields

Gausss Law

Electric Potential

Capacitance and Dielectrics

Current and Resistance

Direct-Current Circuits

Magnetic Fields

Sources of the Magnetic Field

Faradays Law

Inductance

Alternating-Current Circuits

Electromagnetic Waves

The Nature of Light and the Principles of Ray Optics

Image Formation

Wave Optics

Diffraction Patterns and Polarization

Relativity

Introduction to Quantum Physics

Quantum Mechanics

Atomic Physics

Molecules and Solids

Nuclear Structure

Applications of Nuclear Physics

Particle Physics and Cosmology

Filters

The R value of fiberglass batting,3.5 inches thick,is 11 ft²⋅°F⋅h/BTU.What is the thermal conductivity (in BTU/ft⋅°F⋅s)?

An 8 000-kg aluminum flagpole 100-m long is heated by the sun from a temperature of 10°C to 20°C.Find the work done (in J)by the aluminum if the linear expansion coefficient is 24 × 10−⁶ (°C)−¹.(The density of aluminum is 2.7 × 10³ kg/m³ and 1 atm = 1.0 × 10⁵ N/m². )

The R-value of an insulating material is the thickness of the material divided by its thermal conductivity.When an insulating material consists of three layers with R-values R₁,R₂ and R₃,the overall R-value of the insulation is given by

Water at room temperature,20°C,is pumped into a reactor core where it is converted to steam at 200°C.How much heat (in J)is transferred to each kilogram of water in this process? (c_steam = 2 010 J/kg⋅°C;L_steam = 2.26 × 10³ J/g;1 cal = 4.186 J. )

A gas expands from A to B as shown in the graph.Calculate the work (in joules)done by the gas.(1 atm= 1.01 × 10⁵ N/m². )