2017 Spring PHYS 211-E02 (Dook) section: E02) Mark Hughes (Student Bookmark Cour
ID: 1554691 • Letter: 2
Question
2017 Spring PHYS 211-E02 (Dook) section: E02) Mark Hughes (Student Bookmark Course Contents Hw 11 A man stands on a platform that rotating is Chrwaclip 3) A man stands on a platform that is rotating (without friction) with an angular speed of 12 revs his arms ae outr rotational inertia of the system to zao kv m, what is the resuting the system of man weights, and platform about the central axis is 15.00 Ag by moving the weights the man decreases the angular speed of the platform? (rad/s) Submit Answer Tries o/B what is the ratio of the new kinetic energy of the system to the original kinetic energy? Submit Answer Tries o/8 What provided the added kinetic energy? Your receipt no is 158-20so Previous Tries This discussion is closed.Explanation / Answer
wi = 1.2 rev/s = 1.2 x 2pi rad/s
wi = 7.54 rad/s
Applying momentum conservation for system.
Ii wi = If wf
15 x 7.54 = 7.80 wf
wf = 14.5 rad/s ........Ans
Ki = Ii wi^2 /2
KF = If wf^2 /2
Kf/Ki = IF wf^2 / Ii wi^2
= (7.80 x 14.5^2) / (15 x 7.54^2)
= 1.92 .........Ans
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.