All Matches

Solution Library

Expert Answer

Textbooks

Search Textbook questions, tutors and Books

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Tutors
Study Help
Ask a Question

Search
Sign In
Register

study help
physics
thermodynamics

Questions and Answers of Thermodynamics

You make tea with 0.250 kg of 85.0°C water and let it cool to room temperature (20.0°C) before drinking it. (a) Calculate the entropy change of the water while it cools. (b) The cooling process is
Three moles of an ideal gas undergo a reversible isothermal compression at 20.0oC. During this compression, 1850 J of work is done on the gas. What is the change of entropy of the gas?
What is the change in entropy of 0.130 kg of helium gas at the normal boiling point of helium when it all condenses isothermally to 1.00 L of liquid helium? (Hint: See Table 17.4 in Section 17.6.)
(a) Calculate the change in entropy when 1.00 kg of water at 100°C is vaporized and converted to steam at 100°C (see Table 17.4). (b) Compare your answer to the change in entropy when 1.00 kg of
(a) Calculate the change in entropy when 1.00 mol of water (molecular mass 18.0 g/mol) at 100°C evaporates to form water vapor at l00oC. (b) Repeat the calculation of part (a) for 1.00 mol of liquid
If 25.0 g of the metal gallium melts in your hand (see Fig. 17.20), what is the change in entropy of the gallium in this process? What about the change in entropy of your hand? Is it positive or
A box is separated by a partition into two parts of equal volume. The left side of the box contains 500 molecules of nitrogen gas; the right side contains 100 molecules of oxygen gas. The two gases
Two moles of an ideal gas occupy a volume V. The gas expands isothermally and reversibly to a volume 3V. (a) Is the velocity distribution changed by the isothermal expansion? Explain. (b) Use Eq.
A lonely party balloon with a volume of 2.40 L and containing 0.100 mol of air is left behind to drift in the temporarily uninhabited and depressurized International Space Station. Sunlight coming
You design a Carrot engine that operates between temperatures of 500 K and 400 K and produces 2000 J of work in each cycle. (a) Calculate your engine's efficiency. (b) Calculate the amount of beat
You are designing a Carnot engine that has 2 mol of CO2 as its working substance; the gas may be treated as ideal. The gas is to have a maximum temperature of 527°C and a maximum pressure of 5.00
A Carnot engine whose low-temperature reservoir is at -90.0oC has an efficiency of 40.0%. An engineer is assigned the problem of increasing this to 45.0%. (a) By how many Celsius degrees must the
A beat engine takes 0.350 mol of a diatomic ideal gas around the cycle shown in the pV-diagram of fig. 20.24. Process I → 2 is at constant volume, process 2→3 is adiabatic, and process 3
You build a beat engine that takes 1.00 mol of an ideal diatomic gas through the cycle shown in Fig. 20.25.(a) Show that segment ab is an isothermal compression.(b) During which segment(s) of the
A beat pump is a beat engine run in reverse. In winter it pumps heal from the cold air outside into the warmer air inside the building, maintaining the building at a comfortable temperature. In
A beat engine operates using the cycle shown in Fig. 20.26. The working substance is 2.00 mol of helium gas, which reaches a maximum temperature of 327°C. Assume the helium can be treated as an
As a budding mechanical engineer, you are called upon to design a Carnot engine that has 200 mol of a monatomic ideal gas as its working substance and operates from a high-temperature reservoir at
An experimental power plant at the Natural energy Laboratory of Hawaii generates electricity from the temperature gradient of the ocean. The surface and deep-water temperatures are 27°C and 6°C,
What is the thermal efficiency of an engine that operates by taking n moles of diatomic ideal gas through the cycle 1→2 → 3→4 →1 shown in Fig.20.27?
A cylinder contains oxygen at a pressure of 2.00 atm. The volume is 4.00 L. and the temperature is 300 K. Assume that the oxygen may be treated as an ideal gas. The oxygen is carried through the
PercentageState T (oC) P (kPa) V (m3) U (kJ) That Is Liquida 80 2305 0.0682 1969 0b 80 2305 0.00946 1171 100c 5 363 0.2202 1005 54d 5 363 0.4513 1657
A monatomic ideal gas is taken around the cycle shown in Fig. 20.29 in the direction shown in the figure. The path for process c → a is a straight line in the pV-diagram.(a) Calculate Q, W, and
A Stirling-Cycle Engine the Stirling cycle is similar to the Otto cycle, except that the compression and expansion of the gas are done at constant tem- perature, not adiabatically as in c the Otto
A Carnot engine operates between two heat reservoirs at temperatures TH and Tc. An inventor proposes to increase the efficiency by running one engine between TH and an intermediate temperature T’
A typical coal-fired power plant generates 1000 MW of usable power at an overall thermal efficiency of 40%. (a) What is the rate of heat input to the plant? (b) The plant bums anthracite coal, which
Automotive Thermodynamics A Volkswagen Passat has a six-cylinder Otto cycle engine with compression ratio r = 10.6. The diameter of each cylinder, called the bore of the engine, is 82.5 mm. The
An air conditioner operates on 800 W of power and has a performance coefficient of 2.80 with a room temperature of 21.0oC and an outside temperature of 35.0oC. (a) Calculate the rate of heat removal
(b) Apply the result of part (a) to 1.00 kg of water initially at a temperature of 373 K as the heat source for the engine and Tc = 273 K. How much total mechanical work can be performed by the
The maximum power that can be extracted by a wind turbine from an air stream is approximatelyP = kd2v3Where d is the blade diameter, u is the wind speed, and the constant k = 0.5 W· s3/m5.(a)
(a) How much work must a Carnet refrigerator do on a hot day to transfer 1000 J of heat from its interior at l0°C to the outside air at 35.0°C? (b) How much work must the same refrigerator do to
A 0.0500-kg cube of ice at an initial temperature of -15.0°C is placed in 0.600 kg of water at T = 45.0°C in an insulated container of negligible mass. (a) Calculate the final temperature of the
A TS-Diagram (a) Graph a Carnot cycle, plotting Kelvin temperature vertically and entropy horizontally. This is called a temperature-entropy diagram, or TS-diagram. (b) Show that the area under
(a) For the Otto cycle shown in Fig. 20.6, calculate the changes in entropy of the gas in each of the constant-volume processes b → c and d → a in terms of the temperatures Ta Tb Tc and
A physics student immerses one end of a copper rod in boiling water at 100°C and the other end in an ice-water mixture at 0°C. The sides of the rod are insulated. After steady-state conditions have
To heat 1 cup of water (250 cm3) to make coffee, you place an electric heating element in the cup. As the water temperature increases from 20°C to 65°C, the temperature of the heating element
An object of mass m1 specific heat capacity C1 and temperature T1 is placed in contact with a second object of mass m2, specific heat capacity C2, and temperature T2 > T1 . As a result, the
Consider a Diesel cycle that starts (at point a in Fig. 20.7) with air at temperature Ta. The air may be treated as an ideal gas. (a) If the temperature at point c is Tc derive an expression for the
Is it possible for two objects to be in thermal equilibrium if they are not in contact with each other? Explain.
A piece of copper is dropped into a beaker of water. If the water’s temperature rises, what happens to the temperature of the copper? Under what conditions are the water and copper in thermal
In describing his upcoming trip to the Moon, and as portrayed in the movie Apollo 13 (Universal, 1995), astronaut Jim Lovell said, “I’ll be walking in a place where there’s a 400-degree
Rubber has a negative average coefficient of linear expansion. What happens to the size of a piece of rubber as it is warmed?
Explain why a column of mercury in a thermometer first descends slightly and then rises when the thermometer is placed into hot water.
Why should the amalgam used in dental fillings have the same average coefficient of expansion as a tooth? What would occur if they were mismatched?
Markings to indicate length are placed on a steel tape in a room that has a temperature of 22°C. Are measurements made with the tape on a day when the temperature is 27°C too long, too short, or
Determine the number of grams in a mole of the following gases: (a) Hydrogen (b) Helium (c) Carbon monoxide.
What does the ideal gas law predict about the volume of a sample of gas at absolute zero? Why is this prediction incorrect?
An inflated rubber balloon filled with air is immersed in a flask of liquid nitrogen that is at 77 K. Describe what happens to the balloon, assuming that it remains flexible while being cooled.
Two identical cylinders at the same temperature each contain the same kind of gas and the same number of moles of gas. If the volume of cylinder A is three times greater than the volume of cylinder
After food is cooked in a pressure cooker, why is it very important to cool off the container with cold water before attempting to remove the lid?
The shore of the ocean is very rocky at a particular place. The rocks form a cave sloping upward from an underwater opening, as shown in Figure Q19.13a.(a) Inside the cave is a pocket of trapped air.
In Colonization: Second Contact (Harry Turtledove, Ballantine Publishing Group, 1999), the Earth has been partially settled by aliens from another planet, whom humans call Lizards. Laboratory study
The pendulum of a certain pendulum clock is made of brass. When the temperature increases, does the period of the clock increase, decrease, or remain the same? Explain.
An automobile radiator is filled to the brim with water while the engine is cool. What happens to the water when the engine is running and the water is heated? What do modern automobiles have in
Metal lids on glass jars can often be loosened by running hot water over them. How is this possible?
When the metal ring and metal sphere in Figure Q19.18 are both at room temperature, the sphere can just be passed through the ring. After the sphere is heated, it cannot be passed through the ring.
Clearly distinguish among temperature, heat, and internal energy.
Ethyl alcohol has about half the specific heat of water. If equal-mass samples of alcohol and water in separate beakers are supplied with the same amount of energy, compare the temperature increases
A small metal crucible is taken from a 200°C oven and immersed in a tub full of water at room temperature (this process is often referred to as quenching). What is the approximate final equilibrium
What is a major problem that arises in measuring specific heats if a sample with a temperature above 100°C is placed in water?
In a daring lecture demonstration, an instructor dips his wetted fingers into molten lead (327°C) and withdraws them quickly, without getting burned. How is this possible? (This is a dangerous
What is wrong with the following statement? “Given any two objects, the one with the higher temperature contains more heat.”
Why is a person able to remove a piece of dry aluminum foil from a hot oven with bare fingers, while a burn results if there is moisture on the foil?
The air temperature above coastal areas is profoundly influenced by the large specific heat of water. One reason is that the energy released when 1 m3 of water cools by 1°C will raise the
Concrete has a higher specific heat than soil. Use this fact to explain (partially) why cities have a higher average nighttime temperature than the surrounding countryside. If a city is hotter than
Using the first law of thermodynamics, explain why the total energy of an isolated system is always constant.
When a sealed Thermos bottle full of hot coffee is shaken, what are the changes, if any, in (a) The temperature of the coffee (b) The internal energy of the coffee?
Is it possible to convert internal energy to mechanical energy? Explain with examples.
The U.S. penny was formerly made mostly of copper and is now made of copper-coated zinc. Can a calorimetric experiment be devised to test for the metal content in a collection of pennies? If so,
Figure Q20.14 shows a pattern formed by snow on the roof of a barn. What causes the alternating pattern of snow-covered and exposed roof?
Consider the opening photograph for Part 3 on page 578. Discuss the roles of conduction, convection, and radiation in the operation of the cooling fins on the support posts of the Alaskan oil
Why can potatoes be baked more quickly when a metal skewer has been inserted through them?
A piece of paper is wrapped around a rod made half of wood and half of copper. When held over a flame, the paper in contact with the wood burns but the half in contact with the metal does not.
Why do heavy draperies over the windows help keep a home cool in the summer, as well as warm in the winter?
If you wish to cook a piece of meat thoroughly on an open fire, why should you not use a high flame? (Note that carbon is a good thermal insulator.)
In an experimental house, Styrofoam beads were pumped into the air space between the panes of glass in double windows at night in the winter, and pumped out to holding bins during the day. How would
Pioneers stored fruits and vegetables in underground cellars. Discuss the advantages of this choice for a storage site.
The pioneers referred to in the last question found that a large tub of water placed in a storage cellar would prevent their food from freezing on really cold nights. Explain why this is so.
When camping in a canyon on a still night, one notices that as soon as the sun strikes the surrounding peaks, a breeze begins to stir. What causes the breeze?
Updrafts of air are familiar to all pilots and are used to keep non-motorized gliders aloft. What causes these currents?
If water is a poor thermal conductor, why can its temperature be raised quickly when it is placed over a flame?
Why is it more comfortable to hold a cup of hot tea by the handle rather than by wrapping your hands around the cup itself?
If you hold water in a paper cup over a flame, you can bring the water to a boil without burning the cup. How is this possible?
You need to pick up a very hot cooking pot in your kitchen. You have a pair of hot pads. Should you soak them in cold water or keep them dry, to be able to pick up the pot most comfortably?
Suppose you pour hot coffee for your guests, and one of them wants to drink it with cream, several minutes later, and then as warm as possible. In order to have the warmest coffee, should the person
Two identical cups both at room temperature are filled with the same amount of hot coffee. One cup contains a metal spoon, while the other does not. If you wait for several minutes, which of the two
A warning sign often seen on highways just before a bridge is “Caution—Bridge surface freezes before road surface.” Which of the three energy transfer processes discussed in Section 20.7 is
A professional physics teacher drops one marshmallow into a flask of liquid nitrogen, waits for the most energetic boiling to stop, fishes it out with tongs, shakes it off, pops it into his mouth,
In 1801 Humphrey Davy rubbed together pieces of ice inside an ice-house. He took care that nothing in their environment was at a higher temperature than the rubbed pieces. He observed the production
Dalton’s law of partial pressures states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of gases making up the mixture. Give a convincing argument for
One container is filled with helium gas and another with argon gas. If both containers are at the same temperature, which molecules have the higher rms speed? Explain.
A gas consists of a mixture of He and N2 molecules. Do the lighter He molecules travel faster than the N2 molecules? Explain.
Although the average speed of gas molecules in thermal equilibrium at some temperature is greater than zero, the average velocity is zero. Explain why this statement must be true.
When alcohol is rubbed on your body, it lowers your skin temperature. Explain this effect.
A liquid partially fills a container. Explain why the temperature of the liquid decreases if the container is then partially evacuated. (Using this technique, it is possible to freeze water at
A vessel containing a fixed volume of gas is cooled. Does the mean free path of the molecules increase, decrease, or remain constant in the cooling process? What about the collision frequency?
A gas is compressed at a constant temperature. What happens to the mean free path of the molecules in this process?
If a helium-filled balloon initially at room temperature is placed in a freezer, will its volume increase, decrease, or remain the same?
Which is denser, dry air or air saturated with water vapor? Explain.
What happens to a helium-filled balloon released into the air? Will it expand or contract? Will it stop rising at some height?
Why does a diatomic gas have a greater energy content per mole than a monatomic gas at the same temperature?

Showing 700 - 800 of 7587

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Last

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Campus Ambassador

Company Info

Security
Copyrights
Privacy Policy
Terms & Condition
SolutionInn Fee
Scholarship

Services

Sitemap
Fun
Definitions
Become Tutor
Study Help Categories
Recent Questions
Expert Questions

Copyright © 2024 SolutionInn All Rights Reserved.

Get the SolutionInn - Study Help App