-
Section 11.3 Angular Momentum J-s behind
rmv
a
he
ur
265
= ?
a
ter
30. Example 11.1: A 58.1
Iw COMP string and whirled at
18. Express the units of angular momentum (a) using only the funda-
momentum of magr
mental units kilogram, meter, and second; (b) in a form involving
the circular path. Fir
newtons; (c) in a form involving joules.
marw
horizontal and (b) the
19. Use data from Appendix E to make an order-of-magnitude esti-
31. Example 11.2. A stai
mate for the angular momentum of our Solar System about the
Max 27
the end of its lifetime
galactic center.
mu
= 17.293
of radius 4.96 X 10'
20. A gymnast of rotational inertia 63 kg•m? is tumbling head over heels
dwarf of radius 4.21
with angular momentum 460 kg•m?/s. What's her angular speed?
17.99 acted on the core, fine
A 660-g hoop 95 cm in diameter is rotating at 170 rpm about its
32. Example 11.2: Astro
22. A 1.3-th-diameter golf ball has mass 45 g and is spinning at
central axis. What's its angular momentum? L: 1W=0-66*(0-95) x 140x277.10 km and determin
core that collapsed to
3000 rpm. Treating the golf ball as a uniform solid sphere, what's
ing with a period of 4
its angular momentum?
18-3 33. Example 11.2. The s
10-598
rpm
With her arms outstre
Section 11.4 Conservation of Angular Momentum
tational inertia is 3.5
23. A potter's wheel with rotational inertia 6.20 kg•m? is spinning
(Fig. 11.6b), her rot
freely at 20.0 rpm. The potter drops a 2.50-kg lump of clay onto her final spin rate?
L = 6 2 x 2-1 = 12-99~13
- 2x2
22
13= 60.48)" x 2.5 W
W = 2
.
X
z
W = 20x2T
60
²2.1
~
1
12.574