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प्रश्न
Give three examples to illustrate that friction is a necessary evil.
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उत्तर
The examples to illustrate that friction is a necessary evil are:
- If friction were absent, we would not be able to walk.
- Friction is necessary to burn a matchstick.
- It is due to friction that we can write on board by chalk.
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संबंधित प्रश्न
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| Column I | Column II | |
| a) | Static friction | Viscosity |
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