A uniform rod, supported and pivoted at
its midpoint, but initially at rest, has a mass
of 86 g and a length 5 cm. A piece of clay with
mass 21 g and velocity 1.7 m/s hits the very
top of the rod, gets stuck and causes the clay-
rod system to spin about the pivot point O at
the center of the rod in a horizontal plane.
Viewed from above the scheme is
!
!
1.7 m/s

(a) before (b) during (c) after
5 cm
After the collisions the clay-rod system has an
diby (ad33488) – HW8 – mackie – (10612) 3
angular velocity ! about the pivot.
With respect to the pivot point O, what is
the magnitude of the initial angular momen-
tum Li of the clay-rod system?
Answer in units of kgm2/s
014 (part 2 of 3) 10.0 points
With respect to the pivot point O, what is
the final moment of inertia If of the clay-rod
system?
Answer in units of kgm2
015 (part 3 of 3) 10.0 points
The final angular speed !f of the clay-rod
system is
Answer in units of rad/s