Question 1

We are able to define a mechanical equivalent for heat because

Accepted Answer

A) some thermal energy can be converted into mechanical energy. 
B) mechanical energy can be converted into thermal energy. 
C) work can be converted into thermal energy. 
D) some thermal energy can be converted into work. 
E) all of the above can occur. 
A) some thermal energy can be converted into mechanical energy. 
B) mechanical energy can be converted into thermal energy. 
C) work can be converted into thermal energy. 
D) some thermal energy can be converted into work. 
E) all of the above can occur.

Question 2

The air in an automobile engine at 20 $\degree$C is compressed from an initial pressure of 1.0 atm and a volume of 200 cm3 to a volume of 20 cm3.Find the temperature if the air behaves like an ideal gas ($\gamma$= 1.4)and the compression is adiabatic.

Accepted Answer

A) 730 $\degree$C 
B) 460 $\degree$C 
C) 25 $\degree$C 
D) 50 $\degree$C 
E) 20 $\degree$C 
A) 730 $\degree$C 
B) 460 $\degree$C 
C) 25 $\degree$C 
D) 50 $\degree$C 
E) 20 $\degree$C

Question 3

Two kilograms of water at 100 $\degree$C is converted to steam at 1 atm.Find the change in internal energy (in J).(Lv = 2.26 *106 J/kg. )

Accepted Answer

A) 2.1 * 104 
B) 4.5 *106 
C) 3.4 * 105 
D) 4.2 * 106 
E) 2.1 * 106 
A) 2.1 * 104 
B) 4.5 *106 
C) 3.4 * 105 
D) 4.2 * 106 
E) 2.1 * 106

Question 4

Two kilograms of water at 100 $\degree$C is converted to steam at 1 atm.Find the work done (in J).(The density of steam at 100 $\degree$C is 0.598 kg/m3. )

Accepted Answer

A) 3.4 * 105 
B) 1.2 *105 
C) 4.6 * 104 
D) 2.1 * 104 
E) 3.4 * 104 
A) 3.4 * 105 
B) 1.2 *105 
C) 4.6 * 104 
D) 2.1 * 104 
E) 3.4 * 104

Question 5

If 25 kg of ice at 0 $\degree$C is combined with 4 kg of steam at 100 $\degree$C,what will be the final equilibrium temperature (in  $\degree$C)of the system?

Accepted Answer

A) 40 
B) 20 
C) 60 
D) 100 
E) 8 
A) 40 
B) 20 
C) 60 
D) 100 
E) 8

Question 6

A styrofoam container used as a picnic cooler contains a block of ice at 0 $\degree$C.If 225 grams of ice melts in 1 hour,how much heat energy per second is passing through the walls of the container? (The heat of fusion of ice is 3.33 *105 J/kg).

Accepted Answer

The answer of A styrofoam container used as a picnic...

Question 7

Gas in a container expands at a constant pressure of 3 atm.Find the work done (in J)by the gas if the initial volume is 5 liters and the final volume is 10 liters.

Accepted Answer

A) 0 
B) 150 
C) 15 
D) 1 500 
E) 1.5 
A) 0 
B) 150 
C) 15 
D) 1 500 
E) 1.5

Question 8

A team of people who traveled to the North Pole by dogsled lived on butter because they needed to consume 6 000 dietician's Calories each day.Because the ice there is lumpy and irregular,they had to help the dogs by pushing and lifting the load.Assume they had a 16 hour working day and that each person could lift a 500 N load.How many times would a person have to lift this weight 1.00 m upwards in a constant gravitational field where $g = 9.80 \frac { \mathrm { m } } { \mathrm { s } ^ { 2 } }$ to do the work equivalent to 6 000 Calories?

Accepted Answer

A) 50.2 
B) 492 
C) 5 130 
D) 50 200 
E) 492 000 
A) 50.2 
B) 492 
C) 5 130 
D) 50 200 
E) 492 000

Question 9

Find the specific heat (in cal/mole K)of a gas kept at constant volume when it takes 1.0 * 104 J of heat to raise the temperature of 5.0 moles of the gas 200 K above the initial temperature.

Accepted Answer

A) 7.5 
B) 5.0 
C) 2.4 
D) 10 
E) 20 
A) 7.5 
B) 5.0 
C) 2.4 
D) 10 
E) 20

Question 10

Which of the following statements is(are)correct when an ideal gas goes from an initial to a final state in a single process?

Accepted Answer

A) No work is done on or by the gas when the volume remains constant. 
B) No energy is transferred into or out of the gas as heat transfer when the temperature remains constant. 
C) The internal energy of the gas does not change when the pressure remains constant. 
D) All the statements above are correct. 
E) Only statements (a)and (b)above are correct. 
A) No work is done on or by the gas when the volume remains constant. 
B) No energy is transferred into or out of the gas as heat transfer when the temperature remains constant. 
C) The internal energy of the gas does not change when the pressure remains constant. 
D) All the statements above are correct. 
E) Only statements (a)and (b)above are correct.

Question 11

The theorem of equipartition of energy states that the energy each degree of freedom contributes to each molecule in the system (an ideal gas)is

Accepted Answer

A)  $\frac { 1 } { 2 } m v ^ { 2 }$ . 
B)  $\frac { 1 } { 3 } k _ { B } T$ . 
C)  $\frac { 1 } { 2 } k _ { B } T$ . 
D)  $\frac { 3 } { 2 } m v ^ { 2 }$ . 
E)  $\frac { 3 } { 2 } k _ { B } T$ . 
A)  $\frac { 1 } { 2 } m v ^ { 2 }$ . 
B)  $\frac { 1 } { 3 } k _ { B } T$ . 
C)  $\frac { 1 } { 2 } k _ { B } T$ . 
D)  $\frac { 3 } { 2 } m v ^ { 2 }$ . 
E)  $\frac { 3 } { 2 } k _ { B } T$ .

Question 12

Steel blocks A and B,which have equal masses,are at TA = 300  $\degree$C and TB = 400  $\degree$C.Block C,with mC = 2mA,is at TC = 350  $\degree$C.Blocks A and B are placed in contact,isolated,and allowed to come into equilibrium.Then they are placed in contact with block C.At that instant,

Accepted Answer

A) TA = TB C. 
B) TA = TB = TC. 
C) TA = TB > TC. 
D) TA + TB = TC. 
E) TA - TB = TC. 
A) TA = TB C. 
B) TA = TB = TC. 
C) TA = TB > TC. 
D) TA + TB = TC. 
E) TA - TB = TC.

Question 13

A 300-g glass thermometer initially at 25$\degree$C is put into 200 cm3 of hot water at 95$\degree$C.Find the final temperature (in $\degree$C)of the thermometer,assuming no heat flows to the surroundings.(The specific heat of glass is 0.2 cal/g.$\degree$C. )

Accepted Answer

A) 52 
B) 68 
C) 89 
D) 79 
E) 36 
A) 52 
B) 68 
C) 89 
D) 79 
E) 36

Question 14

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$\degree$C,and the temperature of the surroundings is 21$\degree$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.$\degree$C.

Accepted Answer

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

Question 15

A child has a temperature of 101$\degree$F.If her total cross-sectional area is 2 m2,find the energy lost each second (in W)due to radiation,assuming the emissivity is 1.(Assume the room temperature is 70$\degree$F. )

Accepted Answer

A) 217 
B) 180 
C) 90 
D) 68 
E) 850 
A) 217 
B) 180 
C) 90 
D) 68 
E) 850

Question 16

Aluminum rod #1 is 1.0 m long with cross-section area 2.0 cm2.Aluminum rod #2 is 2.0 m long with cross-section area 4.0 cm2.Aluminum rod #3 is 3.0 m long with cross-section area 9.0 cm2.If each rod has the same temperature difference applied across its ends,which rod has the greatest rate of transfer of energy between its ends?

Accepted Answer

A) #1 
B) #2 
C) #3 
D) #2 = #3,both greater than #1 
E) They each have the same rate. 
A) #1 
B) #2 
C) #3 
D) #2 = #3,both greater than #1 
E) They each have the same rate.

Question 17

The molar specific heat at constant pressure at 0$\degree$C of an ideal monatomic gas is

Accepted Answer

A)  $\frac { 1 } { 2 } R$ . 
B) R. 
C)  $\frac { 3 } { 2 } R$ . 
D) 2R. 
E)  $\frac { 5 } { 2 } R$ . 
A)  $\frac { 1 } { 2 } R$ . 
B) R. 
C)  $\frac { 3 } { 2 } R$ . 
D) 2R. 
E)  $\frac { 5 } { 2 } R$ .

Question 18

Duff states that equal masses of all substances have equal changes in internal energy when they have equal changes in temperature.Javan states that the change in internal energy is equal to a constant times the change in temperature for every $\Delta$T,no matter how large or how small $\Delta$T is,but that the constant is different for different substances.Which one,if either,is correct?

Accepted Answer

A) Neither,because the specific heat depends on the substance and may vary with temperature. 
B) Neither,because a change of state may involve release or absorption of latent heat. 
C) Neither because a substance may do work during a temperature change. 
D) All of the statements above are correct. 
E) Only statements (a)and (b)are correct. 
A) Neither,because the specific heat depends on the substance and may vary with temperature. 
B) Neither,because a change of state may involve release or absorption of latent heat. 
C) Neither because a substance may do work during a temperature change. 
D) All of the statements above are correct. 
E) Only statements (a)and (b)are correct.

Question 19

A block of material of mass m and specific heat c falls from height h and reaches speed v just before striking the ground.Its temperature is measured immediately after it strikes the ground.If we ignore any change in temperature owing to interaction with the air,the change in temperature of the block of material is

Accepted Answer

A)  $\Delta T = \frac { v ^ { 2 } } { 2 c }$ . 
B)  $\Delta T = \frac { g h } { c }$ . 
C)  $\Delta T = \frac { v g h } { c }$ . 
D) All of the answers above are correct. 
E) Only (a)and (b)above are correct. 
A)  $\Delta T = \frac { v ^ { 2 } } { 2 c }$ . 
B)  $\Delta T = \frac { g h } { c }$ . 
C)  $\Delta T = \frac { v g h } { c }$ . 
D) All of the answers above are correct. 
E) Only (a)and (b)above are correct.

Question 20

In a thermodynamic process,the internal energy of a system in a container with adiabatic walls decreases by 800 J.Which statement is correct?

Accepted Answer

A) The system lost 800 J by heat transfer to its surroundings. 
B) The system gained 800 J by heat transfer from its surroundings. 
C) The system performed 800 J of work on its surroundings. 
D) The surroundings performed 800 J of work on the system. 
E) The 800 J of work done by the system was equal to the 800 J of heat transferred to the system from its surroundings. 
A) The system lost 800 J by heat transfer to its surroundings. 
B) The system gained 800 J by heat transfer from its surroundings. 
C) The system performed 800 J of work on its surroundings. 
D) The surroundings performed 800 J of work on the system. 
E) The 800 J of work done by the system was equal to the 800 J of heat transferred to the system from its surroundings.

Exam 17: Energy in Thermal Processes: the First Law of Thermodynamics

We are able to define a mechanical equivalent for heat because

The air in an automobile engine at 20 °\degree° C is compressed from an initial pressure of 1.0 atm and a volume of 200 cm3 to a volume of 20 cm3.Find the temperature if the air behaves like an ideal gas ( γ\gammaγ = 1.4)and the compression is adiabatic.

Two kilograms of water at 100 °\degree° C is converted to steam at 1 atm.Find the change in internal energy (in J).(Lv = 2.26 *106 J/kg. )

Two kilograms of water at 100 °\degree° C is converted to steam at 1 atm.Find the work done (in J).(The density of steam at 100 °\degree° C is 0.598 kg/m3. )

If 25 kg of ice at 0 °\degree° C is combined with 4 kg of steam at 100 °\degree° C,what will be the final equilibrium temperature (in °\degree° C)of the system?

A styrofoam container used as a picnic cooler contains a block of ice at 0 °\degree° C.If 225 grams of ice melts in 1 hour,how much heat energy per second is passing through the walls of the container? (The heat of fusion of ice is 3.33 *105 J/kg).

Gas in a container expands at a constant pressure of 3 atm.Find the work done (in J)by the gas if the initial volume is 5 liters and the final volume is 10 liters.

Find the specific heat (in cal/mole K)of a gas kept at constant volume when it takes 1.0 * 104 J of heat to raise the temperature of 5.0 moles of the gas 200 K above the initial temperature.

Which of the following statements is(are)correct when an ideal gas goes from an initial to a final state in a single process?

The theorem of equipartition of energy states that the energy each degree of freedom contributes to each molecule in the system (an ideal gas)is

Steel blocks A and B,which have equal masses,are at TA = 300 °\degree° C and TB = 400 °\degree° C.Block C,with mC = 2mA,is at TC = 350 °\degree° C.Blocks A and B are placed in contact,isolated,and allowed to come into equilibrium.Then they are placed in contact with block C.At that instant,

A 300-g glass thermometer initially at 25 °\degree° C is put into 200 cm3 of hot water at 95 °\degree° C.Find the final temperature (in °\degree° C)of the thermometer,assuming no heat flows to the surroundings.(The specific heat of glass is 0.2 cal/g. °\degree° C. )

A child has a temperature of 101 °\degree° F.If her total cross-sectional area is 2 m2,find the energy lost each second (in W)due to radiation,assuming the emissivity is 1.(Assume the room temperature is 70 °\degree° F. )

The molar specific heat at constant pressure at 0 °\degree° C of an ideal monatomic gas is

In a thermodynamic process,the internal energy of a system in a container with adiabatic walls decreases by 800 J.Which statement is correct?

Introduction and Vectors

Motion in One Dimension

Motion in Two Dimensions

The Laws of Motion

More Applications of Newtons Laws

Energy of a System

Conservation of Energy

Momentum and Collisions

Relativity

Rotational Motion

Gravity,planetary Orbits,and the Hydrogen Atom

Oscillatory Motion

Mechanical Waves

Superposition and Standing Waves

Fluid Mechanics

Temperature and the Kinetic Theory of Gases

Heat Engines,entropy,and the Second Law of Thermodynamics

Electric Forces and Electric Fields

Electric Potential and Capacitance

Current and Direct Current Circuits

Magnetic Forces and Magnetic Fields

Faradays Law and Inductance

Electromagnetic Waves

Reflection and Refraction of Light

Image Formation by Mirrors and Lenses

Wave Optics

Quantum Physics

Atomic Physics

Nuclear Physics

Particle Physics

Filters

The air in an automobile engine at 20 $\degree$ C is compressed from an initial pressure of 1.0 atm and a volume of 200 cm³ to a volume of 20 cm³.Find the temperature if the air behaves like an ideal gas ( $\gamma$ = 1.4)and the compression is adiabatic.

Two kilograms of water at 100 $\degree$ C is converted to steam at 1 atm.Find the change in internal energy (in J).(L_v = 2.26 *10⁶ J/kg. )

Two kilograms of water at 100 $\degree$ C is converted to steam at 1 atm.Find the work done (in J).(The density of steam at 100 $\degree$ C is 0.598 kg/m³. )

If 25 kg of ice at 0 $\degree$ C is combined with 4 kg of steam at 100 $\degree$ C,what will be the final equilibrium temperature (in $\degree$ C)of the system?

A styrofoam container used as a picnic cooler contains a block of ice at 0 $\degree$ C.If 225 grams of ice melts in 1 hour,how much heat energy per second is passing through the walls of the container? (The heat of fusion of ice is 3.33 *10⁵ J/kg).

Find the specific heat (in cal/mole K)of a gas kept at constant volume when it takes 1.0 * 10⁴ J of heat to raise the temperature of 5.0 moles of the gas 200 K above the initial temperature.

Steel blocks A and B,which have equal masses,are at T_A = 300 $\degree$ C and T_B = 400 $\degree$ C.Block C,with m_C = 2m_A,is at T_C = 350 $\degree$ C.Blocks A and B are placed in contact,isolated,and allowed to come into equilibrium.Then they are placed in contact with block C.At that instant,

A 300-g glass thermometer initially at 25 $\degree$ C is put into 200 cm³ of hot water at 95 $\degree$ C.Find the final temperature (in $\degree$ C)of the thermometer,assuming no heat flows to the surroundings.(The specific heat of glass is 0.2 cal/g. $\degree$ C. )

A child has a temperature of 101 $\degree$ F.If her total cross-sectional area is 2 m²,find the energy lost each second (in W)due to radiation,assuming the emissivity is 1.(Assume the room temperature is 70 $\degree$ F. )

The molar specific heat at constant pressure at 0 $\degree$ C of an ideal monatomic gas is