NDSU- North Dakota State... B My Courses - Blackboard L. LON-CAPA Walking on a C

Question

NDSU- North Dakota State... B My Courses - Blackboard L. LON-CAPA Walking on a C... C Chegg Study | Guided Solu...+ triton physics.ndsunodak.edu/res/ndsu/kyletstrand/Phys211Fall2015Homework12/WalkingOnCircular latform problem?symb= uploaded%2h Q Search A large horizontal crcular platform (M=97.9 kg, r=4.57 m rotates about a frictionless vertical axle. A student m=72.09 kg walks slowly from the rim of the platform toward the center. The angular velocity of the system is 3.4 rad/s when the student is at the rim Find the moment of inertia of platform through the center with respect to the z-axis Submit Answer Tries 0/5 Find the moment of inertia of the student about the center axis (while standing at the rim) of the platform Submit Answer Tries 0/5 Find the moment of inertia of the student about the center axis while the student is standing 1.12 m from the center of the platform Submit Answer Tries 0/5 Find the angular speed when the student is 1.12 m from the center of the platform Submit Answer Tries 0/5 .illi ) 6:29 PM 11/23/2015

Explanation / Answer

Given that

Cicular platform of mass(M) =97.9kg

Radius (r) =4.57m

Mass of the student is (m) =72.09kg

The moment of inertia when a student at rim is I =(1/2)Mr2+mr2

=0.5*97.9*(4.57)2+(72.09)(4.57)2 =1022.315+1505.592

=2527.907kg.m2

Given that

Angular speed (w) =3.4rad/s

Moment inertia when student at a distance d' =1.12m is

I' =(1/2)Mr2+Md'2

=0.5*97.9*(4.57)2+(97.9*(1.12)2=1022.315+122.805=1145.120kg.m2

Now from the conservation of angular momentum

Iw =I'w'

Therefore the required angualr speed is w' =Iw/I' =(2527.907kg.m2)(3.4)/1145.120kg.m2=7.505rad/s

Related Questions

Navigate

• Browse (All)
• Browse N
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.