Closed System

Definition

A closed system is a physical system that does not exchange matter with its surroundings but can exchange energy in the form of heat or work. This concept is crucial in understanding how energy conservation principles apply within a defined boundary, which influences various thermodynamic processes and behaviors.

5 Must Know Facts For Your Next Test

1. In a closed system, energy can be transferred in and out as heat or work, but the mass remains constant within the system's boundaries.
2. The first law of thermodynamics, which focuses on conservation of energy, is often applied to closed systems to analyze energy changes during processes.
3. A common example of a closed system is a sealed container of gas, where energy can be added or removed as heat without any gas escaping.
4. Closed systems are contrasted with open systems, which can exchange both energy and matter with their surroundings, leading to different thermodynamic behaviors.
5. In analyzing closed systems, changes in internal energy, enthalpy, and temperature are important metrics for understanding how the system responds to energy inputs or outputs.

Review Questions

• How does a closed system differ from an open system in terms of matter and energy exchange?
  • A closed system differs from an open system primarily in its ability to exchange matter. In a closed system, while matter cannot enter or exit the defined boundaries, energy can still be exchanged as heat or work. In contrast, an open system allows both matter and energy to flow in and out freely, making its analysis different in terms of thermodynamic behavior.
• Discuss the implications of applying the first law of thermodynamics to a closed system during a thermodynamic process.
  • Applying the first law of thermodynamics to a closed system reveals how energy is conserved during thermodynamic processes. It states that the change in internal energy of the system is equal to the heat added to the system minus the work done by the system. This relationship helps in understanding how different processes affect the internal energy, providing insights into how systems respond to energy inputs and outputs.
• Evaluate how understanding closed systems contributes to advancements in engineering applications such as engines or refrigerators.
  • Understanding closed systems is essential for engineers designing engines or refrigerators because it allows them to predict how these systems will behave under different conditions. By analyzing energy transfers without worrying about mass flow, engineers can optimize performance through efficiency improvements and better energy management. This knowledge facilitates the development of more effective thermal management strategies and contributes significantly to innovations in mechanical design and sustainability efforts.

Related terms

Isolated System: An isolated system is a specific type of closed system that does not exchange either matter or energy with its surroundings.

Heat Transfer: Heat transfer is the movement of thermal energy from one object or system to another due to a temperature difference.

Work: Work is the energy transfer that occurs when an object is moved by a force over a distance.