Closed System

Definition

A closed system is a thermodynamic system that does not exchange matter, but can exchange energy, with its surroundings. It is an isolated system that is self-contained and does not interact with the external environment in terms of mass transfer, while energy transfer is still possible.

5 Must Know Facts For Your Next Test

1. In a closed system, the total mass of the system remains constant, as no matter is allowed to enter or leave the system.
2. Energy can still be exchanged between a closed system and its surroundings, but the total energy of the system and its surroundings remains constant.
3. Closed systems are often used in physics and engineering to model and analyze various phenomena, such as the behavior of gases, the conservation of energy, and the dynamics of mechanical systems.
4. The concept of a closed system is crucial in understanding Newton's First Law of Motion, as it helps explain the principle of inertia and the behavior of objects in the absence of external forces.
5. Closed systems are also central to the study of mechanical energy and the conservation of energy, as the total mechanical energy of a closed system remains constant unless work is done on the system or by the system.

Review Questions

• Explain how the concept of a closed system relates to Newton's First Law of Motion and the principle of inertia.
  • In a closed system, there are no external forces acting on the system, which means that an object within the closed system will maintain its state of rest or uniform motion unless acted upon by an unbalanced internal force. This is the essence of Newton's First Law of Motion, also known as the principle of inertia. The closed system provides the ideal conditions for observing and understanding inertia, as the absence of external influences allows the object to continue its state of motion or rest without interference.
• Describe the role of a closed system in the conservation of mechanical energy.
  • In a closed system, the total mechanical energy, which is the sum of kinetic energy and potential energy, is conserved. This means that the total mechanical energy of the system remains constant over time, unless work is done on the system or by the system. The conservation of mechanical energy is a fundamental principle in physics and is essential for understanding the behavior of various mechanical systems, such as pendulums, projectile motion, and energy transformations in machines. The closed system provides the necessary isolation from external influences to observe and analyze the conservation of mechanical energy.
• Analyze the differences between a closed system, an open system, and an isolated system, and explain how these distinctions impact the exchange of matter and energy within the system.
  • The key distinction between a closed system, an open system, and an isolated system lies in the exchange of matter and energy with the surroundings. A closed system does not allow for the exchange of matter, but it can exchange energy with its surroundings. An open system, on the other hand, can exchange both matter and energy with its surroundings. An isolated system is the most restrictive, as it does not allow for the exchange of either matter or energy. These differences have significant implications for the behavior and analysis of the systems. In a closed system, the total mass remains constant, while energy can be transformed or transferred; in an open system, both mass and energy can be exchanged; and in an isolated system, neither mass nor energy can be exchanged with the external environment, leading to the conservation of the total energy within the system.

Related terms

Open System: An open system is a system that exchanges both matter and energy with its surroundings, having interactions with the external environment.

Isolated System: An isolated system is a closed system that does not exchange either matter or energy with its surroundings, being completely separated from the external environment.

Conservation of Energy: The principle that states that the total energy of an isolated system is constant; it is said to be conserved over time. Energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another.