A diathermic wall is defined as one which____________________?
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Answer: B. permits thermal interaction
Explanation
A diathermic wall is defined as a thermal boundary that freely permits thermal interaction between systems. This type of partition allows heat to transfer easily from one thermodynamic system to another. It contrasts with adiabatic walls, which completely prevent any thermal energy transfer across the boundary. Thermodynamic boundaries classify systems based on whether they permit mass, work, or heat interactions. Real world metal walls often act as diathermic boundaries because metals conduct thermal energy rapidly. Thermal equilibrium between two connected systems requires a diathermic wall separating them.
Heat exchanger designs rely on diathermic walls to transfer thermal energy between fluids efficiently. Boiler tubes act as diathermic barriers transferring furnace combustion heat into internal feed water. Insulated thermos containers use adiabatic rather than diathermic boundaries to prevent heat loss. Preventing thermal interaction describes an adiabatic wall rather than a diathermic partition. Encouraging or discouraging heat transfer are descriptive modifiers, but the formal definition is permitting thermal interaction. Stating that diathermic walls do not exist is false as they are standard thermodynamic boundary models.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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