Question
How Does Ideal Machine Differ from a Practical Machine ?
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Answer
| Ideal machine | Practical machine |
| 1. Efficiency is 100%. | 1. Efficiency is less than 100% |
| 2. Its parts are weightless, elastic and perfectly smooth. | 2. Its parts are not weightless, elastic or perfectly smooth. |
| 3. There is no loss in energy due to friction | 3. There is always some loss of energy due to friction |
| 4. Work output of such a machine is equal to the work input. | 4. Work output is always less than the work input. |
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