An isolated system is defined as one in which_____________________?
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Answer: B. neither mass nor energy crosses the boundaries of the system
Explanation
An isolated system is completely sealed, meaning neither mass nor energy crosses its boundaries. Total energy and total mass within the system remain strictly constant over time. No heat transfer, work interactions, or mass flow occur with the external environment. Isolated systems are idealized theoretical constructs used in thermodynamic analysis. The universe as a whole is often considered the ultimate isolated thermodynamic system. Entropy within an isolated system can never decrease during any spontaneous process.
Insulated containers like ideal thermos flasks approximate isolated systems in experiments. Theoretical physics relies on isolated system models to demonstrate conservation laws. Long-term energy studies consider isolated boundaries to evaluate total entropy changes. Option A describes a closed system where energy can transfer but mass cannot. Option C describes an open system where both mass and energy cross boundaries. Option D describes an impossible system boundary condition violating basic thermodynamics.
- Subject
- Engineering
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- Mechanical Engineering
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- —
- Difficulty
- medium
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