Total angular momentum of a sphere that had both a linear v and an angular v?

1. Mar 17, 2010

therest

1. The problem statement, all variables and given/known data
Find net angular momentum for a soccer ball (moment of inertia=2/3mr^2) that's going 3.6 m/s to the right and 28.5 radians per second clockwise at the same time.
R=0.142 m
m=0.678 kg

2. Relevant equations
L=(perpendicular component of r)mv
L=Iw

3. The attempt at a solution
L=rmvsinθ, but L also equals I*angular velocity, a rotational analog... What if both a rotational and translational velocity exist? do I add them based on these 2 equations, or what? What about the right-hand rule?

2. Mar 18, 2010

vela

Staff Emeritus
Remember that angular momentum is a vector. You need to vector add the two contributions from the rotational and translational motion of the ball. To do this, you need to know the direction of these contributions, which you determine using the various right-hand rules.