Acceleration directions and friction.

[SaxonMilton]

Ok, I am analysing the situation in the attached image, and I am trying to find the frictional force between the nylon string and the top of the piping, but I am not sure what the value of acceleration will be. I understand how to do this when there is only acceleration due to gravity, but with this, centripetal acceleration is involved. Do I need to use vector resolution and find the total acceleration?

 

[alex2344]

Ok, I am analysing the situation in the attached image, and I am trying to find the frictional force between the nylon string and the top of the piping, but I am not sure what the value of acceleration will be. I understand how to do this when there is only acceleration due to gravity, but with this, centripetal acceleration is involved. Do I need to use vector resolution and find the total acceleration?

Ok, its very easy. Use total acceleration

 

[lep11]

What are the forces acting on the system?

 

[SaxonMilton]

Only gravity, and then also centripetal force once the rubber stopper begins spinning. But there is also the friction between the string and the pipe

 

[PeterO]

Only gravity, and then also centripetal force once the rubber stopper begins spinning. But there is also the friction between the string and the pipe

Compared to the other forces involved, that friction is negligible.

 

[SaxonMilton]

Compared to the other forces involved, that friction is negligible.

Yes, we also thought so, but we ran an experiment, and we found after comparing our results to what the values really should be using v = √(Fr/m), our values seemed to increase more so than the true values, so we believe that the additional frictional force is contributing and increasing the speed.

 

[PeterO]

Yes, we also thought so, but we ran an experiment, and we found after comparing our results to what the values really should be using v = √(Fr/m), our values seemed to increase more so than the true values, so we believe that the additional frictional force is contributing and increasing the speed.

Was your piping a glass tube with the ends rounded by heating?

How were you measuring V. Why not start with 4∏²rm / T² rather than mv²/r - as it is easier to measure the Period.

 

[haruspex]

Yes, we also thought so, but we ran an experiment, and we found after comparing our results to what the values really should be using v = √(Fr/m), our values seemed to increase more so than the true values, so we believe that the additional frictional force is contributing and increasing the speed.

Pls explain more about the experimental procedure, what was measured, and the results.