Solving a Spinning Bike Wheel Homework Problem

AI Thread Summary
The discussion revolves around a homework problem involving the direction of a spinning bike wheel hung from a pivot. Participants express confusion about the problem's details, particularly the missing image and how the wheel's orientation affects its motion. There is uncertainty about the correct answer, with one participant initially believing the wheel turns downward but later realizing it turns counterclockwise when viewed from above. The lack of clarity in the problem's presentation leads to suggestions for reposting the question for better visibility. Overall, the thread highlights the importance of clear problem statements in physics homework.
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Homework Statement


{Number 5 on attachment. It has picture.}

When a spinning bike wheel is placed hor-
izontally, hung from a pivot at one end, the
axis of rotation of the wheel will swing in a
horizontal circle.


In which direction does it turn (as viewed
from above)?
1. downward
2. horizontally, CCW
3. upward
4. horizontally, CW


Homework Equations


Any? I'm unsure.


The Attempt at a Solution


I was thinking that it was downward, but I'm not sure how to prove my answer. (We're supposed to show work.) Any help?
 

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I could not find the question or picture of a bicycle wheel in the attachment. I can't wrap my mind around "hung from a pivot at one end". I would think we would have to know from which end or which way the wheel is spinning to distinguish between answers.
 
Delphi51 said:
I could not find the question or picture of a bicycle wheel in the attachment. I can't wrap my mind around "hung from a pivot at one end". I would think we would have to know from which end or which way the wheel is spinning to distinguish between answers.

It was problem five on the attachment. I opened it up to check and if you read that problem, that's it.
 
I see problem 1, 2, 3 . . . and then it jumps to 7 or 8.
A search for the word "bike" in the pdf document returns "not found".
 
What about this upload?

I just don't get it because I see it. It's supposed to be on a column on the right side in the pdf.

The Torque is on the right side, going upwards. The wheel is to the left of it on an axis that starts where the Torque is. The wheel is turned a little from our view but if you look at it dead on, it's going counter clockwise. The arrow is going counter clock wise.
 

Attachments

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I see it now! Not at all what it appeared to be from the words alone. Unfortunately I forget how to do it.
I suggest you post the problem again; people might not want to step into a thread with 6 posts.
 
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