Can something moving linearly without rotation have anguar momentum?

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A point mass can possess angular momentum even when moving linearly without rotation, as angular momentum is defined relative to a reference point. In the discussed scenario, the sticky putty thrown at a stationary wheel contributes angular momentum despite its straight-line motion. This is due to the distance from the reference point, which is factored into the angular momentum calculation. The conservation of angular momentum applies here, as the system's total angular momentum remains constant when no external torque is present. Thus, the putty's linear motion still results in angular momentum relative to the wheel's position.
nabeel17
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I was doing a question in Taylor book (example 3.3) where a sticky putty is thrown at a stationary wheel. To solve it we use conservation of angular momentum. What I am confused about is that the wheel is initially at rest and has no angular momentum initially. But when the putty is thrown at it the wheel starts spinning and gains angular momentum. Since angular momentum must be conserved (external torque is 0 so angular momentum conserved) there must be some inital angular momentum from the putty.

So my question is even though the putty is thrown in a straight line and has no spin or rotational motion, it still posses angular momentum?
 
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nabeel17 said:
So my question is even though the putty is thrown in a straight line and has no spin or rotational motion, it still posses angular momentum?
Yes.

Even a point mass has angular momentum with respect to some reference frame. That essentially is how angular momentum is defined. The angular momentum of a system of particles is the sum of the angular momenta of the individual particles.
 
D H said:
Yes.

Even a point mass has angular momentum with respect to some reference frame. That essentially is how angular momentum is defined. The angular momentum of a system of particles is the sum of the angular momenta of the individual particles.

Ok so with respect to some origin, a point mass will have angular momentum given by rxp where where r is the distance from the origin. Even if it appears to be going straight with no rotation correct? So angular momentum is always defined with respect to an origin
 
Exactly.
 
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