Free Thermodynamics MCQs with Answers
714 Thermodynamics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Thermal equilibrium and heat explain how temperature and energy transfer are related, while molar specific heats describe the heat required by a gas at constant volume or constant pressure. The first law connects heat supplied, work done and change in internal energy, with sign conventions kept distinct from temperature changes.
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Read the Thermodynamics notesFree MDCAT chapter notes with key terms714 questions · page 30 of 36
- A. Escape of air from burst tyre
- B. Cloud formation
- C. Slow expansion
- D. Rapid compression
Explanation: Cloud formation is not an adiabatic process. It involves various processes such as condensation and evaporation, which typically involve…
Correct answer: Cloud formation- A. All heat can be converted to work
- B. Heat flows spontaneously from hot to cold
- C. Internal energy is always conserved
- D. Work cannot be converted to heat
Explanation: The second law states that heat flows spontaneously from a hotter body to a colder one, increasing the entropy of the universe, unless…
Correct answer: Heat flows spontaneously from hot to cold- A. Boyle's law
- B. Isothermal process
- C. General gas law
- D. Charles's law
- E. Henry's law
Explanation: Charles's law, discovered by Jacques Charles, states that for a fixed amount of gas at constant pressure, the volume is directly…
Correct answer: Charles's law- A. 500 mm of Hg
- B. 900 mm of Hg
- C. 1,100 mm of Hg
- D. 1,270 mm of Hg
- E. 1,500
Explanation: Solution: This problem can be solved by ideal gas equation; PV=nRTSince, the temperature remains constant, therefore: Given: Initial…
Correct answer: 1,270 mm of Hg- A. Zeroth law of thermodynamics
- B. 1st law of thermodynamics
- C. 2nd law of thermodynamics
- D. 1st and 2nd law of thermodynamics
Explanation: According to this law,it's impossible for an engine to extract heat from a hot reservoir and convert it completely into useful work.
Correct answer: 2nd law of thermodynamics- A. The pressure exerted by a gas is proportional to mean square velocity of the molecules
- B. The pressure exerted by the gas is proportional to the root mean square velocity of the molecules
- C. The root mean square velocity is inversely proportional to the temperature
- D. The mean translational K.E. of the molecule is directly proportional to the absolute temperature
Explanation: "The equation KE=(3RT)/(2Nٖₐ) gives a new definition of temperature according to which the kelvin temperature of a gas is directly…
Correct answer: The mean translational K.E. of the molecule is directly proportional to the absolute temperature- A. 98.6
- B. 40
- C. 37
- D. 459.4
Explanation: Option A: A temperature of 98.6 degrees Fahrenheit is equivalent to 37 degrees Celsius.
Correct answer: 37- A. 6.68 x 10^5 J
- B. 6.68 x 10^5 kJ
- C. 668 J
- D. 6688 kJ
Explanation: m=2 kg , L=332J/gQ=mLQ=(2×1000)(332)Q=(2000)(332)Q=664000Q=6.64×105 J
Correct answer: 6.68 x 10^5 J- A. Energy travels from the larger object to the smaller object
- B. Energy travels from the object with more mass to the one with less mass
- C. Energy travels from the object at higher temperature to the object at lower temperature
- D. Energy does not travel
Explanation: If two objects at different temperatures are brought in contact with each other, energy is transferred from the hotter object (that is…
Correct answer: Energy travels from the object at higher temperature to the object at lower temperature- A. 1 K
- B. 100k
- C. 273.16k
- D. 0K
Explanation: The triple point of pure water is at 0.01°C (273.16K, 32.01°F)
Correct answer: 273.16k- A. 1.5 kg of the material is to be heated by 7.0 C°
- B. 3.0 kg of the material is to be heated by 3.5 C°
- C. 0.50 kg of the material is to be heated by 21 C°
- D. The amount of heat required is the same in each of the three previous cases
Explanation: When an object is heated, it's temperature changes over a period of time.
Correct answer: The amount of heat required is the same in each of the three previous cases- A. 62 mins
- B. 62 secs
- C. 1.5 hour
- D. 0.5 hour
Explanation: Option A is correct since we know that,P = Q/t t = Q/ Pt= mc / pSo t = 500 x 2230 / 300 = 3717s t = 3717 / 60 = 62 mins
Correct answer: 62 mins- A. Work
- B. Enthalpy
- C. Internal energy
- D. Pressure
Explanation: The thermodynamic state of a system refers to the temperature, pressure and quantity of substance present.
Correct answer: Work594. When a gas is compressed isothermally, the product of its pressure and volume during the process is:
- A. not constant
- B. constant
- C. zero
- D. proportional
Explanation: According to Boyle's law, which applies to an ideal gas undergoing an isothermal process, the product of pressure and volume remains…
Correct answer: constant- A. Non-spontaneous reaction
- B. Endothermic process
- C. Exothermic process
- D. Spontaneous reaction
Explanation: Endothermic processes are the ones that absorb heat from the surroundings.
Correct answer: Endothermic process- A. 1/Kg
- B. 4.18 J/Kg.K
- C. 4180 J/kg.K
- D. 2090 J/kg.K
Explanation: Option C is correct since 4180 J/Kg K is the correct value of the specific heat capacity of water.Option A is incorrect since the value…
Correct answer: 4180 J/kg.K- A. 3.23 x 10^-21 J
- B. 4.11 x 10^-21 J
- C. 6.21 x 10^-21 J
- D. 7.71. x 107-21 J
- E. 9.11 x 10^7-21 J
Explanation: To calculate the average translational kinetic energy of molecules in a gas at a given temperature, we can use the equation:K.E.
Correct answer: 6.21 x 10^-21 J- A. The pipe expanded due to the hot air, and then contracted back again
- B. The tap got deformed because of the hot air
- C. The hot air caused adhesion between the rubber and plastic
- D. None of the above options are correct
Explanation: Applying heat from the hair dryer caused the rubber pipe to expand due to the increase in temperature.
Correct answer: The pipe expanded due to the hot air, and then contracted back again- A. Water equivalent
- B. Temperature gradient
- C. Thermal capacity
- D. Specefic heat
Explanation: Option C is correct.The heat that is given to a body that raises its temperature by 1°C is the thermal capacity of the body.Thermal…
Correct answer: Thermal capacity- A. A man, he, I have never seen before, was asking about you.
- B. A man, whoever I have never seen before, was asking about you.
- C. A man, who have never seen before, was asking about you.
- D. A man, whom I have never seen before, was asking about you.
Explanation: This option is correct. "Whom" is the correct object pronoun to use in this context.
Correct answer: A man, whom I have never seen before, was asking about you.