# I Can we say Angular Velocity is a 'moment' of tangential velocity?

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1. Aug 10, 2017

### Soumitra

If a rigid link pin joint-fixed on ground and is rotating freely about the same point with uniform ang. vel., can we say the vector form of angular vel. (omega) is nothing but moment of the tangential (perpendicular) vel. at the other end?

2. Aug 10, 2017

### pixel

The moment of the velocity (r x v) would give you the direction of the angular velocity vector but not its magnitude as ω ≠ rv but rather v = rω.

3. Aug 10, 2017

### Soumitra

Thanks

4. Aug 11, 2017

### Soumitra

So can we say that vector form of tangential velocity is 'moment' of angular velocity, right?

5. Aug 11, 2017

### sophiecentaur

I think the answer must be No, strictly. Surely you should say that the angular velocity is the 'moment' of the tangential velocity. That would make more sense.

6. Aug 11, 2017

### Zachary Burell

you can say anything, choose whatever semantics you wish but that will only cloud what is going on and you will still have the same equation, physics power derives from expressing laws and and phenomena in terms of precise mathematical relationships, the word you use to refer to the precise mathematical relationships is arbitrary and will not add any substance or clarity, if you want gain intuition write down the equation for the most general case (no numbers, all symbols) and then one can proceed from this expression to different specific special cases; playing around with these equations, staring at them, and letting our subconscious bat that around all are the ways physicists gain deeper insight into a problem, not by trying to come up with the newest trendy bumper sticker catch phrase, which is ambiguous because its bound to be interpreted as many different ways as people who hear it (the major handicap of non mathematical sciences and why they will all be subsumed by physics in due course as is already beginning to take place in chem and bio and climatology etc

Last edited: Aug 11, 2017
7. Aug 13, 2017

### Soumitra

Don't get me wrong but, It's hard to digest!; So (in short) did you mean 'What's in a name'?

8. Aug 14, 2017

### Dr.D

The term "moment" has a well defined meaning in the area of mechanics. Expressed vectorially, the moment of a vector V is r x V, where r is the position vector of the point where V acts with respect to a specified reference point.

You can say anything you want (provided you live in an area with freedom of speech), but you will not communicate clearly with others unless you observe the well established meanings of words.

You say "it's hard to digest!" I strongly suggest that you think about it until you do understand it, and work with what others have already given you in terms of terminology, rather than wanting to invent your own terms.