Problem .22
A brass rod is 185 cm long and 1.60 cm in diameter. What force must be applied to each end of the rod to prevent it from contracting when it is cooled from 120.0°C to 10.0°C?
Problem 6a
Calculate the one temperature at which Fahrenheit and Celsius thermometers agree with each other.
Problem 6b
Calculate the one temperature at which Fahrenheit and Kelvin thermometers agree with each other
Problem 7
The pressure of a gas at the triple point of water is atm. If its volume remains unchanged, what will its pressure be at the temperature at which CO2 solidifies?
Problem 10
A constant-volume gas thermometer registers an absolute pressure corresponding to mm of mercury when in contact with water at the triple point. What pressure does it read when in contact with water at the normal boiling point?
Problem 16
A geodesic dome constructed with an aluminum framework is a nearly perfect hemisphere; its diameter measures 55.0 m on a winter day at a temperature of -15°C. How much more interior space does the dome have in the summer, when the temperature is 35°C?
Problem 17.41
A 6.00-kg piece of solid copper metal at an initial temperature T is placed with 2.00 kg of ice that is initially at -20.0°C. The ice is in an insulated container of negligible mass and no heat is exchanged with the surroundings. After thermal equilibrium is reached, there is 1.20 kg of ice and 0.80 kg of liquid water. What was the initial temperature of the piece of copper?
Problem 18
A steel tank is completely filled with 1.90 m3 of ethanol when both the tank and the ethanol are at 32.0°C. When the tank and its contents have cooled to 18.0°C, what additional volume of ethanol can be put into the tank?
Problem 21a
Steel train rails are laid in 12.0-m-long segments placed end to end. The rails are laid on a winter day when their temperature is -9.0°C. How much space must be left between adjacent rails if they are just to touch on a summer day when their temperature is 33.0°C?
Problem 24b
In an effort to stay awake for an all-night study session, a student makes a cup of coffee by first placing a 200-W electric immersion heater in 0.320 kg of water. How much time is required? Assume that all of the heater's power goes into heating the water.
Problem 26a
In very cold weather a significant mechanism for heat loss by the human body is energy expended in warming the air taken into the lungs with each breath. On a cold winter day when the temperature is -20°C, what amount of heat is needed to warm to body temperature (37°C) the 0.50 L of air exchanged with each breath? Assume that the specific heat of air is 1020 J/kg K and that 1.0 L of air has mass 1.3 × 10-3 kg.
Problem 31
While painting the top of an antenna 225 m in height, a worker accidentally lets a 1.00-L water bottle fall from his lunchbox. The bottle lands in some bushes at ground level and does not break. If a quantity of heat equal to the magnitude of the change in mechanical energy of the water goes into the water, what is its increase in temperature?
Problem 32
A nail driven into a board increases in temperature. If we assume that 60% of the kinetic energy delivered by a 1.80 kg hammer with a speed of 7.80 m/s is transformed into heat that flows into the nail and does not flow out, what is the temperature increase of an 8.00 g aluminum nail after it is struck ten times?
Problem 34
You have 750 g of water at 10.0°C in a large insulated beaker. How much boiling water at 100.0°C must you add to this beaker so that the final temperature of the mixture will be 75°C?
Problem 36
One suggested treatment for a person who has suffered a stroke is immersion in an ice-water bath at 0°C to lower the body temperature, which prevents damage to the brain. In one set of tests, patients were cooled until their internal temperature reached 32.0°C. To treat a 70.0 kg patient, what is the minimum amount of ice (at 0°C) you need in the bath so that its temperature remains at 0°C? The specific heat of the human body is 3480 J/kg C°, and recall that normal body temperature is 37.0°C.
Problem 37
A blacksmith cools a 1.20 kg chunk of iron, initially at 650.0°C, by trickling 15.0°C water over it. All of the water boils away, and the iron ends up at 120.0°C. How much water did the blacksmith trickle over the iron?
Problem 38
A copper calorimeter can with mass 0.100 kg contains 0.160 kg of water and 0.0180 kg of ice in thermal equilibrium at atmospheric pressure. If 0.750 kg of lead at 255°C is dropped into the calorimeter can, what is the final temperature? Assume that no heat is lost to the surroundings.
Problem 39
A copper pot with a mass of 0.500 kg contains 0.170 kg of water, and both are at 20.0°C. A 0.250-kg block of iron at 85.0°C is dropped into the pot. Find the final temperature of the system, assuming no heat loss to the surroundings.
Problem 42
An ice-cube tray of negligible mass contains 0.290 kg of water at 18.0°C. How much heat must be removed to cool the water to 0.00°C and freeze it? Express your answer in joules, calories, and Btu.
Problem 49
An asteroid with a diameter of 10 km and a mass of 2.60 × 1015 kg impacts the earth at a speed of 32.0 km/s, landing in the Pacific Ocean. If 1.00% of the asteroid's kinetic energy goes to boiling the ocean water (assume an initial water temperature of 10.0°C), what mass of water will be boiled away by the collision? (For comparison, the mass of water contained in Lake Superior is about 2 × 1015 kg.)
Problem 50
A laboratory technician drops a -kg sample of unknown solid material, at °C, into a calorimeter. The calorimeter can, initially at °C, is made of kg of copper and contains kg of water. The final temperature of the calorimeter can and contents is °C. Compute the specific heat of the sample.
Problem 51
An insulated beaker with negligible mass contains kg of water at °C. How many kilograms of ice at °C must be dropped into the water to make the final temperature of the system °C?
Problem 52
A -kg silver ingot is taken from a furnace, where its temperature is °C, and placed on a large block of ice at °C. Assuming that all the heat given up by the silver is used to melt the ice, how much ice is melted?
Problem 54b
Two rods, one made of brass and the other made of copper, are joined end to end. The length of the brass section is m and the length of the copper section is m. Each segment has cross-sectional area m2. The free end of the brass segment is in boiling water and the free end of the copper segment is in an ice–water mixture, in both cases under normal atmospheric pressure. The sides of the rods are insulated so there is no heat loss to the surroundings. What mass of ice is melted in min by the heat conducted by the composite rod?
Problem 57a
A carpenter builds an exterior house wall with a layer of wood cm thick on the outside and a layer of Styrofoam insulation cm thick on the inside wall surface. The wood has , and the Styrofoam has . The interior surface temperature is °C, and the exterior surface temperature is °C. What is the temperature at the plane where the wood meets the Styrofoam?
Problem 57b
A carpenter builds an exterior house wall with a layer of wood cm thick on the outside and a layer of Styrofoam insulation cm thick on the inside wall surface. The wood has , and the Styrofoam has . The interior surface temperature is °C, and the exterior surface temperature is °C. What is the rate of heat flow per square meter through this wall?
Problem 58a
An electric kitchen range has a total wall area of m2 and is insulated with a layer of fiberglass cm thick. The inside surface of the fiberglass has a temperature of °C, and its outside surface is at °C. The fiberglass has a thermal conductivity of . What is the heat current through the insulation, assuming it may be treated as a flat slab with an area of m2 ?
Problem 66
The emissivity of tungsten is . A tungsten sphere with radius cm is suspended within a large evacuated enclosure whose walls are at K. What power input is required to maintain the sphere at K if heat conduction along the supports is ignored?
Ch 17: Temperature and Heat