A uniform disk of mass 80 kg and radius 0.5 m is mounted on frictionless bearings so it canrotate freely around an axis through its center. A cord is wrapped around the rim of the diskand pulled with a force of 40 N. Initially it is not spinning.40 N40 N(a) How much work has the force done after 8m of the cord have been pulled starting from rest?(b) Now what is the angular speed?(c) Extra If the 40-N force is replaced by a 40-N weight, what is the angular speed of the cylinderafter 8.0 m of cord have unwound? Constants and other possibly useful numbersg = 9.8m/s?G = 6.67 × 10-11 Nm/kg?c= 3 x 10°m/sRadius of the Moon: 1.74 x 106mMass of the Sun: 2 x 1030kgRadius of the Sun: 6.957 x 10°mMass of an electron me =9.11 x 10-31kgMass of a proton mp1.67 x 10-27kg%3DAverage distance between the Moon and Earth:3.84 x 10 mAverage distance between Sun and Earth: 1.5 x1011mMass of Earth: 6 x 1024kgRadius of Earth: 6.4 x 106mMass of the Moon: 7.35 x 1022kgMoments of Inertia:R+ R2.MR²12I =Em;r? Iring = MIdisk =ML Igphere =M R= Icylinder =MR IrodI disk%3D%D%3D12The vector product or cross product between two vectors A and B can be calculated as follows:If you know the angle 0 between the two vectors, find the magnitude of the product |C| = |Ã × B| =|A||B| sin 0 and find the direction using the right-hand-rule.%3D

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A uniform disk of mass 80 kg and radius 0.5 m is mounted on frictionless bearings so it can rotate freely around an axis through its center. A cord is wrapped around the rim of the disk and pulled with a force of 40 N. Initially it is not spinning. 40 N 40 N (a) How much work has the force done after 8m of the cord have been pulled starting from rest? (b) Now what is the angular speed? (c) Extra If the 40-N force is replaced by a 40-N weight, what is the angular speed of the cylinder after 8.0 m of cord have unwound?

A uniform disk of mass 80 kg and radius 0.5 m is mounted on frictionless bearings so it can rotate freely around an axis through its center. A cord is wrapped around the rim of the disk and pulled with a force of 40 N. Initially it is not spinning. 40 N 40 N (a) How much work has the force done after 8m of the cord have been pulled starting from rest? (b) Now what is the angular speed? (c) Extra If the 40-N force is replaced by a 40-N weight, what is the angular speed of the cylinder after 8.0 m of cord have unwound?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter13: Rotation Ii: A Conservation Approach

Section: Chapter Questions

Problem 7PQ: A 12.0-kg solid sphere of radius 1.50 m is being rotated by applying a constant tangential force of...

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