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| <span><img src="../../img/book.png"></span><span>Savchenko Solutions</span> | | <span><img src="../../img/book.png"></span><span>Savchenko Solutions</span> |
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| <p class="author"> | | <p class="author"> |
| Solutions of Savchenko Problems in Physics <br> | | Solutions of Savchenko Problems in Physics <br> |
| <i><b>knowledge must be free</b></i> | | <i><b>knowledge must be free</b></i> |
| </p> | | </p> |
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| <h3 id="back-link"><a href="../../#2.7">$\leftarrow$Back</a></h3> | | <h3 id="back-link"><a href="../../#2.7">$\leftarrow$Back</a></h3> |
| | | |
| <h3> Statement </h3> | | <h3> Statement </h3> |
| <p> | | <p> |
| $2.7.19^*.$ A uniform heavy rope, the ends of which are fixed on the same vertical, covers | | $2.7.19^*.$ A uniform heavy rope, the ends of which are fixed on the same vertical, covers |
| a weightless hoop. How fast does the hoop fall when released? | | a weightless hoop. How fast does the hoop fall when released? |
| </p> | | </p> |
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| <figure> | | <figure> |
| <img src="2.7.19.png" | | <img src="2.7.19.png" |
| loading="lazy" width="160" /> | | loading="lazy" width="160" /> |
| <figcaption> | | <figcaption> |
| For problem $2.7.19^*$ | | For problem $2.7.19^*$ |
| </figcaption> | | </figcaption> |
| </figure> | | </figure> |
| </center> | | </center> |
| <p> | | <p> |
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| </p> | | </p> |
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| <h3>Solution</h3> | | <h3>Solution</h3> |
| <p> | | <p> |
| | | |
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| <center> | | <center> |
| <figure> | | <figure> |
| <img src="2.7.19_1.png" | | <img src="2.7.19_1.png" |
| loading="lazy" width="200" /> | | loading="lazy" width="200" /> |
| <figcaption> | | <figcaption> |
| Rotation of the hoop | | Rotation of the hoop |
| </figcaption> | | </figcaption> |
| </figure> | | </figure> |
| </center> | | </center> |
| <p> | | <p> |
| | | |
| Hoof's moment of inertia | | Hoof's moment of inertia |
| $$I_0=mR^2$$ | | $$I_0=mR^2$$ |
