11.2 Thermodynamics

• Thermodynamics is concerned with the laws governing the transfer and conversion of energy
• What is one example of the scope of thermodynamics in engineering physics?

  Analyzing heat engine efficiency
• What does ΔU represent in the First Law of Thermodynamics?

  Change in internal energy
• Heat is energy transferred due to temperature difference
• What does the Second Law of Thermodynamics state about energy transformations?

  They are not perfectly efficient
• Reversible processes have 100% efficiency


  True
• What is the value of Absolute Zero in Celsius?

  -273.15 °C
• What is the Third Law of Thermodynamics?

  Entropy approaches a minimum
• At 0 Kelvin, entropy is ideally zero for perfect crystalline structures.


  True
• Engineering physics applies principles from various areas of physics to solve practical engineering problems.
• Match the concept with its description:

  Thermodynamics ↔️ Study of energy transformations

  Engineering Physics ↔️ Application of physics principles
• The First Law of Thermodynamics can be expressed as ΔU = Q - W.
• What is entropy a measure of?

  Disorder within a system
• What is the efficiency of a heat engine that outputs 500 J of work for every 1000 J of heat input?

  50%
• At Zero Kelvin, entropy is ideally zero for perfect crystalline structures.

  True
• What is the purpose of understanding the Third Law of Thermodynamics?

  Optimize low-temperature processes
• In an isothermal process, the temperature remains constant
• What is an example of an adiabatic process?

  Rapid compression of gas
• What are the four processes of the Carnot Cycle in order?

  1️⃣ Isothermal expansion

  2️⃣ Adiabatic expansion

  3️⃣ Isothermal compression

  4️⃣ Adiabatic compression
• The Carnot Efficiency establishes an upper limit on the efficiency of any heat engine
• What is the focus of thermodynamics in engineering physics?

  Design of engineering systems
• What is thermodynamics the study of?

  Energy and its transformations
• Engineering physics applies thermodynamics to solve practical engineering problems


  True
• The First Law of Thermodynamics states that energy is always conserved
• Heat and work are both forms of energy transfer


  True
• A gas cylinder receives 200 J of heat and expands, doing 100 J of work. What is the change in the internal energy of the gas?

  100 J
• Entropy is a measure of the disorder or randomness within a system.
• A heat engine outputs 500 J of work for every 1000 J of heat input. What is its efficiency?

  50%
• At Absolute Zero, entropy is ideally zero for perfect crystalline structures
• As the temperature of a system approaches absolute zero, its entropy approaches a minimum value.
• What is thermodynamics concerned with?

  Energy and its transformations
• What is one application of thermodynamics in engineering physics?

  Analyzing heat engine efficiency
• What does the First Law of Thermodynamics state?

  Energy is always conserved
• Heat and work have the same effect on a system's internal energy.

  False
• Order the characteristics of reversible and irreversible processes:

  1️⃣ Reversible: Ideal efficiency (100%)

  2️⃣ Reversible: No entropy increase

  3️⃣ Irreversible: Less than 100% efficiency

  4️⃣ Irreversible: Entropy increases
• What is the definition of efficiency in thermodynamics?

  Ratio of useful output to input
• The Second Law of Thermodynamics implies that entropy decreases with each process.

  False
• The Third Law of Thermodynamics states that as temperature approaches Absolute Zero, the entropy of the system approaches a minimum value
• Match the temperature state with the corresponding entropy state:

  High Temperature ↔️ High disorder

  As temperature approaches 0K ↔️ Minimum disorder

  0K ↔️ No disorder for ideal crystals
• In an adiabatic process, there is no heat exchange with the surroundings.


  True