====== Disobedient Spool ======

{{tag>wood yoyo inertia axis rotation untagged located}}

<WRAP box right>
{{DisobedientSpool_001.jpg?400|}}

// //
</WRAP>

===== Description =====

Effective display of axis of rotation


Updated on: 06/13/13  inertia



===== Purpose =====


To illustrate the importance of locating the correct axis of rotation in any rotational situation.  



===== Apparatus =====


Spool, string  



===== Setup =====


Place spool on a table and pull string horizontally. The spool will wind the string up and move in the same direction. A suggested teaching device is to set up a problem with given dimensions, moment of inertia and applied force and to postulate that the spool will accelerate in the opposite direction to the force with an acceleration, alpha. Complete the problem obtaining the (apparent) puzzling negative value of alpha. Then bring out the spool and demonstrate that the physics as calculated is correct.  



===== Notes =====



<WRAP group>
<WRAP half column>

</WRAP>
<WRAP half column>

</WRAP>
</WRAP>


<WRAP box>
<WRAP centeralign> // Demo room information // 
</WRAP>
<WRAP tablewidth 100%>
| **Location** | N2 |
| **Maker** | Unknown |
| **Current State** | Working |
</WRAP>
</WRAP>