# Homework Help: Angular velocity of midpoint

1. Jan 23, 2006

### teng125

does anybody knows how to find the angular velocity of the midpoint of a bar??

pls help.........

2. Jan 23, 2006

### civil_dude

I think you're going to have to provide additional information...

3. Jan 23, 2006

### teng125

no,let say the angular velocity of a bar is given but what is the angular velocity of the midpoint of the bar itself

4. Jan 23, 2006

### andrewchang

i would say that the midpoint has the same angular velocity.

5. Jan 23, 2006

### durt

A single point can't have angular velocity about itself, can it? (assuming the "midpoint" is also the pivot point)

6. Jan 23, 2006

### civil_dude

I do believe that for a rigid body, the angulare velocity is the same for all points on the body.

7. Jan 23, 2006

### durt

But the center point is not moving, so it has no angular velocity. I guess it doen't really matter since the point has no mass.

8. Jan 23, 2006

### civil_dude

I think that the axis, which runs through the point of rotation, will be rotating, although since r = o, it will have no tangential velocity.

9. Jan 23, 2006

### andrewchang

actually, the center point is moving. it just happens to be spinning in the same place.

10. Jan 23, 2006

### zthavan

the centre point moves

11. Jan 23, 2006

### durt

A point can't "spin." A very, very small object can, but not a point.

12. Jan 23, 2006

### andrewchang

Last edited by a moderator: May 2, 2017
13. Jan 23, 2006

### fargoth

this is a stupid argument :tongue2:

i thought id enter it, but... nah...

14. Jan 23, 2006

### andrewchang

i agree... i think i'll stop now.