Question 1

The process in which heat flows by the mass movement of molecules from one place to another is known as

Accepted Answer

A) conduction. 
B) convection. 
C) radiation. 
A) conduction. 
B) convection. 
C) radiation.

Question 2

The coefficient of linear expansion of copper is 17 × 10-6 K-1 and that of steel is 12 × 10-6 K-1.At 12°C a steel rod has a diameter of 2.540 cm and a copper pipe has a diameter of 2.536 cm.If they are heated together to a higher temperature,which one of the following quantities is closest to the common temperature at which the steel rod will fit snugly in the copper pipe?

Accepted Answer

A) 310°C 
B) 330°C 
C) 340°C 
D) 350°C 
E) 380°C 
A) 310°C 
B) 330°C 
C) 340°C 
D) 350°C 
E) 380°C

Question 3

At room temperature,a typical person loses energy to the surroundings at the rate of 62 W.If this energy loss has to be made up by an equivalent food intake,how many kilocalories (food calories)does this person need to consume every day just to make up this heat loss? (1 cal = 4.186 J)

Accepted Answer

A) 1000 kcal 
B) 1100 kcal 
C) 1300 kcal 
D) 1500 kcal 
E) 1600 kcal 
A) 1000 kcal 
B) 1100 kcal 
C) 1300 kcal 
D) 1500 kcal 
E) 1600 kcal

Question 4

Object 1 has three times the specific heat capacity and four times the mass of Object 2.The two objects are given the same amount of heat.If the temperature of Object 1 changes by an amount ΔT,the change in temperature of Object 2 will be

Accepted Answer

A) ΔT. 
B)    ΔT. 
C)    ΔT. 
D) 6ΔT. 
E) 12ΔT. 
A) ΔT. 
B)    ΔT. 
C)    ΔT. 
D) 6ΔT. 
E) 12ΔT.

Question 5

A steel bridge is 1000 m long at -20°C in winter.What is the change in length when the temperature rises to 40°C in summer? The average coefficient of linear expansion of this steel is 11 × 10-6 K-1.

Accepted Answer

A) 0.33 m 
B) 0.44 m 
C) 0.55 m 
D) 0.66 m 
A) 0.33 m 
B) 0.44 m 
C) 0.55 m 
D) 0.66 m

Question 6

A mercury thermometer has a glass bulb of interior volume 0.100 cm3 at 10°C.The glass capillary tube above the bulb has an inner cross-sectional area of 0.012 mm2.The coefficient of volume expansion of mercury is 1.8 × 10-4 K-1.If the expansion of the glass is negligible,how much will the mercury rise in the capillary tube when the temperature rises from 5°C to 35°C if the bulb was full at 5°C?

Accepted Answer

A) 0.45 mm 
B) 4.5 mm 
C) 45 mm 
D) 45 cm 
A) 0.45 mm 
B) 4.5 mm 
C) 45 mm 
D) 45 cm

Question 7

A thermally isolated system is made up of a hot piece of aluminum and a cold piece of copper,with the aluminum and the copper in thermal contact.The specific heat capacity of aluminum is more than double that of copper.Which object experiences the greater temperature change during the time the system takes to reach thermal equilibrium?

Accepted Answer

A) the copper 
B) the aluminum 
C) Neither one;both of them experience the same size temperature change. 
D) It is impossible to tell without knowing the masses. 
E) It is impossible to tell without knowing the volumes. 
A) the copper 
B) the aluminum 
C) Neither one;both of them experience the same size temperature change. 
D) It is impossible to tell without knowing the masses. 
E) It is impossible to tell without knowing the volumes.

Question 8

A brass rod is 69.5 cm long and an aluminum rod is 49.3 cm long when both rods are at an initial temperature of 0° C.The rods are placed in line with a gap of 1.2 cm between them,as shown in the figure.The distance between the far ends of the rods is maintained at 120.0 cm throughout.The temperature of both rods is raised equally until they are barely in contact.At what temperature does contact occur? The coefficients of linear expansion of brass and aluminum are 2.0 × 10-5 K-1 (brass)and 2.4 × 10-5 K-1 (aluminum).

Accepted Answer

A) 470°C 
B) 440°C 
C) 420°C 
D) 490°C 
E) 510°C 
A) 470°C 
B) 440°C 
C) 420°C 
D) 490°C 
E) 510°C

Question 9

A heat-conducting rod that is wrapped in insulation is constructed with a 0.15-m length of alloy A and a 0.40-m length of alloy B,joined end-to-end.Both pieces have cross-sectional areas of 0.0020 m2.The thermal conductivity of alloy B is known to be 1.8 times as great as that for alloy A.The end of the rod in alloy A is maintained at a temperature of 10°C,and the other end of the rod is maintained at an unknown temperature.When steady state flow has been established,the temperature at the junction of the alloys is measured to be 40° C,and the rate of heat flow in the rod is measured at 56 W.What is the temperature of the end of the rod in alloy B?

Accepted Answer

A) 80°C 
B) 84°C 
C) 88°C 
D) 92°C 
E) 96°C 
A) 80°C 
B) 84°C 
C) 88°C 
D) 92°C 
E) 96°C

Question 10

When 50 g of a certain material at 100°C is mixed with 100 g of water at 0°C,the final temperature is 40°C.What is the specific heat of the material? The specific heat of water is 1.00 kcal/kg ∙ °C.

Accepted Answer

A) 0.33 kcal/kg ∙ °C 
B) 0.75 kcal/kg ∙ °C 
C) 1.3 kcal/kg ∙ °C 
D) 7.5 kcal/kg ∙°C 
A) 0.33 kcal/kg ∙ °C 
B) 0.75 kcal/kg ∙ °C 
C) 1.3 kcal/kg ∙ °C 
D) 7.5 kcal/kg ∙°C

Question 11

A carpenter is driving a 15.0-g steel nail into a board.His 1.00-kg hammer is moving at 8.50 m/s when it strikes the nail.Half of the kinetic energy of the hammer is transformed into heat in the nail and does not flow out of the nail.What is the increase in temperature of the nail after the three blows that the carpenter needs to drive the nail in completely? The specific heat of steel is 448 J/kg ∙ K.

Accepted Answer

A) 8.1 K 
B) 3.6 K 
C) 1.8 K 
D) 2.7 K 
E) 7.7 K 
A) 8.1 K 
B) 3.6 K 
C) 1.8 K 
D) 2.7 K 
E) 7.7 K

Question 12

The coefficient of linear expansion of aluminum is 24.0 × 10-6 K-1,and the density of aluminum at 0°C is 2.70 × 103 kg/m3.What is the density of aluminum at 300°C?

Accepted Answer

A) 3.93 × 103 kg/m3 
B) 2.73 × 103 kg/m3 
C) 2.70 × 103 kg/m3 
D) 2.67 × 103 kg/m3 
E) 2.64 × 103 kg/m3 
A) 3.93 × 103 kg/m3 
B) 2.73 × 103 kg/m3 
C) 2.70 × 103 kg/m3 
D) 2.67 × 103 kg/m3 
E) 2.64 × 103 kg/m3

Question 13

At what,if any,temperature are the numerical readings on the Fahrenheit and Celsius scales the same?

Accepted Answer

A) -30° 
B) -40° 
C) -50° 
D) -60° 
E) They can never read the same because they are based on different zeroes. 
A) -30° 
B) -40° 
C) -50° 
D) -60° 
E) They can never read the same because they are based on different zeroes.

Question 14

On his honeymoon,James Joule attempted to explore the relationships between various forms of energy by measuring the rise of temperature of water which had fallen down a waterfall on Mount Blanc.What maximum temperature rise would one expect for a waterfall with a vertical drop of 20 m? The specific heat of water is 4186 J/kg ∙ K.

Accepted Answer

A) 0.047°C 
B) 0.053°C 
C) 0.064°C 
D) 0.071°C 
A) 0.047°C 
B) 0.053°C 
C) 0.064°C 
D) 0.071°C

Question 15

A sphere of surface area 1.25 m2 and emissivity 1.0 is at a temperature of 100°C.At what rate does it radiate heat into empty space? (σ = 5.67 × 10-8 W/m2 ∙ K4)

Accepted Answer

A) 7.1 W 
B) 0.71 mW 
C) 1.4 kW 
D) 9.9 mW 
E) 3.7 W 
A) 7.1 W 
B) 0.71 mW 
C) 1.4 kW 
D) 9.9 mW 
E) 3.7 W

Question 16

The thermal conductivity of a certain concrete is 0.80 W/m .K and the thermal conductivity of a certain wood is 0.10 W/m ∙ K.How thick would a solid concrete wall have to be in order to have the same rate of heat flow through it as an 8.0-cm thick wall made of solid wood? Both walls have the same surface area and the same temperature difference across their faces.

Accepted Answer

A) 53 cm 
B) 64 cm 
C) 71 cm 
D) 85 cm 
A) 53 cm 
B) 64 cm 
C) 71 cm 
D) 85 cm

Question 17

A concrete wall of a cold storage room measures 3.0 m high,5.0 m wide,and 20 cm thick.The inside wall is to be covered by a layer of wood in order to reduce the rate of heat flow through the wall by 90 percent.The inner surface of the wooden wall is maintained at -10°C and the outer surface of the concrete wall is at 20°C.The thermal conductivities of concrete and wood are 0.80 W/m ∙ K (concrete)and 0.040 W/m ∙ K (wood).What should be the thickness of the layer of wood?

Accepted Answer

A) 60 mm 
B) 70 mm 
C) 80 mm 
D) 90 mm 
E) 100 mm 
A) 60 mm 
B) 70 mm 
C) 80 mm 
D) 90 mm 
E) 100 mm

Question 18

A solid cylindrical bar conducts heat at a rate of 25 W from a hot to a cold reservoir under steady state conditions.If both the length and the diameter of this bar are doubled,the rate at which it will conduct heat between these reservoirs will be

Accepted Answer

A) 200 W. 
B) 100 W. 
C) 50 W. 
D) 25 W. 
E) 12.5 W. 
A) 200 W. 
B) 100 W. 
C) 50 W. 
D) 25 W. 
E) 12.5 W.

Question 19

A blacksmith is flattening a steel plate having dimensions 10 cm × 15 cm × 1 mm.He has heated the plate to 900 K.If the emissivity of the plate is 0.75,at what rate does it lose energy by radiation? Ignore any heat exchange with the surroundings.(σ = 5.67 × 10-8 W/m2 ∙ K4)

Accepted Answer

A) 360 W 
B) 760 W 
C) 790 W 
D) 850 W 
E) 880 W 
A) 360 W 
B) 760 W 
C) 790 W 
D) 850 W 
E) 880 W

Question 20

As shown in the figure,a bimetallic strip,consisting of metal G on the top and metal H on the bottom,is rigidly attached to a wall at the left.The coefficient of linear thermal expansion for metal G is greater than that of metal H.If the strip is uniformly heated,it will

Accepted Answer

A) curve upward. 
B) curve downward. 
C) remain horizontal,but get longer. 
D) remain horizontal,but get shorter. 
E) bend in the middle. 
A) curve upward. 
B) curve downward. 
C) remain horizontal,but get longer. 
D) remain horizontal,but get shorter. 
E) bend in the middle.

Exam 16: Temperature and Heat

The process in which heat flows by the mass movement of molecules from one place to another is known as

At room temperature,a typical person loses energy to the surroundings at the rate of 62 W.If this energy loss has to be made up by an equivalent food intake,how many kilocalories (food calories)does this person need to consume every day just to make up this heat loss? (1 cal = 4.186 J)

Object 1 has three times the specific heat capacity and four times the mass of Object 2.The two objects are given the same amount of heat.If the temperature of Object 1 changes by an amount ΔT,the change in temperature of Object 2 will be

A steel bridge is 1000 m long at -20°C in winter.What is the change in length when the temperature rises to 40°C in summer? The average coefficient of linear expansion of this steel is 11 × 10-6 K-1.

When 50 g of a certain material at 100°C is mixed with 100 g of water at 0°C,the final temperature is 40°C.What is the specific heat of the material? The specific heat of water is 1.00 kcal/kg ∙ °C.

The coefficient of linear expansion of aluminum is 24.0 × 10-6 K-1,and the density of aluminum at 0°C is 2.70 × 103 kg/m3.What is the density of aluminum at 300°C?

At what,if any,temperature are the numerical readings on the Fahrenheit and Celsius scales the same?

A sphere of surface area 1.25 m2 and emissivity 1.0 is at a temperature of 100°C.At what rate does it radiate heat into empty space? (σ = 5.67 × 10-8 W/m2 ∙ K4)

A solid cylindrical bar conducts heat at a rate of 25 W from a hot to a cold reservoir under steady state conditions.If both the length and the diameter of this bar are doubled,the rate at which it will conduct heat between these reservoirs will be

A blacksmith is flattening a steel plate having dimensions 10 cm × 15 cm × 1 mm.He has heated the plate to 900 K.If the emissivity of the plate is 0.75,at what rate does it lose energy by radiation? Ignore any heat exchange with the surroundings.(σ = 5.67 × 10-8 W/m2 ∙ K4)

As shown in the figure,a bimetallic strip,consisting of metal G on the top and metal H on the bottom,is rigidly attached to a wall at the left.The coefficient of linear thermal expansion for metal G is greater than that of metal H.If the strip is uniformly heated,it will

Introduction to Physics

One-Dimensional Kinematics

Vectors in Physics

Two-Dimensional Kinematics

Newtons Laws of Motion

Applications of Newtons Laws

Work and Kinetic Energy

Potential Energy and Conservation of Energy

Linear Momentum and Collisions

Rotational Kinematics and Energy

Rotational Dynamics and Static Equilibrium

Gravity

Oscillations About Equilibrium

Waves and Sound

Fluids

Phases and Phase Changes

The Laws of Thermodynamics

Electric Charges, Forces, and Fields

Electric Potential and Electric

Electric Current and Direct-Current Circuits

Magnetism

Magnetic Flux and Faradays Law of Induction

Alternating-Current Circuits

Electromagnetic Waves

Geometrical Optics

Optical Instruments

Physical Optics: Interference and Diffraction

Relativity

Quantum Physics

Atomic Physics

Nuclear Physics and Nuclear Radiation

Filters

A steel bridge is 1000 m long at -20°C in winter.What is the change in length when the temperature rises to 40°C in summer? The average coefficient of linear expansion of this steel is 11 × 10^-6 K^-1.

The coefficient of linear expansion of aluminum is 24.0 × 10^-6 K^-1,and the density of aluminum at 0°C is 2.70 × 10³ kg/m³.What is the density of aluminum at 300°C?

A sphere of surface area 1.25 m² and emissivity 1.0 is at a temperature of 100°C.At what rate does it radiate heat into empty space? (σ = 5.67 × 10^-8 W/m² ∙ K⁴)

A blacksmith is flattening a steel plate having dimensions 10 cm × 15 cm × 1 mm.He has heated the plate to 900 K.If the emissivity of the plate is 0.75,at what rate does it lose energy by radiation? Ignore any heat exchange with the surroundings.(σ = 5.67 × 10^-8 W/m² ∙ K⁴)