Quick question about RPMs (revolutions per minute)

[MrBond]

I'm working on a project for work, and I'm trying to remember if the RPM at the edge of a disk attached to a shaft is less then that of the shaft itself. My head hurts too bad to remember the forumla for figuring it out, if it even exists. Any ideas?

 

[snakesnfrogs]

I would think that it would be MORE at the edge, not less

 

[Napalm381]

The revolutions per minute will be exactly the same. The linear distance traveled by a point on the disk increases as you go out farther from the center. Don't confuse the two.

 

[geno]

No matter the size, it's still rotating the same number of times as the rest of the assembly. The speed on the outer edge will be greater though.

 

[Capn]

if the disk is rigidly attached to the shaft the angular velocity would be the same for both components. If you're thinking linear velocity at some radius, the linear velocity increases linearly with radius at constant angular velocity.

 

[TimeThrash]

Napalm comin' through with the physics skillz.
Sucks trying to unconfuse yourself on the fly.
Tt

 

[MrBond]

Thats right....and I should be able to figure out speed based on one RPM of the disk (in this case, a mixer, but it's spinning around in a circle). I know the speed of the shaft, but thats not what I needed...

All I kept thinking about was that one calvin and hobbes strip where calvin's dad tried to explain how a point on the outer edge of a record player appears to travel faster, and calvin gets all confused. And my head really hurts

Thanks guys!