Lecture 21 Conservation of Angular Momentum
1
Review: Analogies between Linear and Rotational Motion
•
TABLE of anaologies
1.1
Angular Momentum of a single particle
•
For a single particle a distance
r
⊥
from the point about which it rotates (like one of the
balls in the barbell example)
~
L
=
~
r
×
~
p
=
mvr
⊥
•
Amount of rotation depends on “impact parameter” (distance from the axis of rotation).
DRAW  rotation max when it hits one end.
•
Conceptually we can see that it is also proportional to
mv
of particle.
•
So, angular momentum conceptually is related to how much spin is induced when the
“particle” hits the stick. In this case, the angular momentum is transferred to the stick
in the same way that momentum is transferred in a linear collision. The single particle
has angular momentum!
•
IMPORTANT  de±ned relative to a reference point!!! Stick example  could be pinned
about another point (instead of center). Amount of rotation will depend on where particle
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '08
 Millan
 Angular Momentum, Momentum, Rotation

Click to edit the document details