NASA puts a satellite into space that consists of two small 32-kg balls connecte
ID: 1409613 • Letter: N
Question
NASA puts a satellite into space that consists of two small 32-kg balls connected by a 12-m long light cable, as shown in the figure. The entire system is initially rotating at 4.0 rpm about an axis perpendicular to the cable at the center of mass. Motors in each mass reel out more cable so that the masses double their separation to 24 m. What is the final rotational speed (in rpm) of the balls? If the initial rotational kinetic energy of the system was K. what is the final rotational kinetic energy in terms of K?Explanation / Answer
a) By conservation of angular momentum,
Iw = constant
when separation doubles, moment of inertia becomes four times, and angular velocity becomes one-fourth.
new w = 1 rpm
b) KE = 0.5 i w^2
when i becomes four times and w becomes one-fourth,
KE becomes one fourth,
final KE = K/4
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.