Which statement regarding the differences between a machine and a structure is false___________________?
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Answer: D. Efficiency of machines as well as structures is below 100%
Explanation
The efficiency of both machines and structures is always below one hundred percent. Frictional losses and internal damping ensure that efficiency never reaches ideal perfection. Therefore, stating that efficiency is below one hundred percent for both is true, making statement D false as a distinction. Machines transmit mechanical work and motion, whereas structures transmit forces without relative motion. Energy losses due to friction affect all mechanical devices and civil engineering structures alike. Distinguishing criteria between machines and structures rely on relative motion, not efficiency limits.
Mechanical engineers analyze machine efficiencies to minimize power losses in industrial gearboxes. Civil engineers evaluate structural efficiency in terms of load-bearing capacity and material weight. Understanding thermodynamic losses is essential for evaluating overall mechanical system performance. Option A correctly distinguishes machines transmitting work from structures transmitting static forces. Option B correctly identifies relative motion as existing in machines but absent in structures. Option C correctly notes that machines modify movement while structures primarily support loads.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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