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