Two wheels of moment of inertia 9.8 kg.nf and 7.8 kg.nf are set in rotation with angular speed 2.9 rad/s and 8.5 rad/s, respectively. When they are coupled face to face (as shown in the following figure) they rotate with a common angular speed co due to frictional forces, then what is the change in kinetic energy (0) of the wheels due to frictional forces? Before coupling After coupling Select one: a. -68.10 b.136.20 C 68.10 O d.-136.20

Two wheels of moment of inertia 9.8 kg.nf and 7.8 kg.nf are set in rotation with angular speed 2.9 rad/s and 8.5 rad/s, respectively. When they are coupled face to face (as shown in the following figure) they rotate with a common angular speed co due to frictional forces, then what is the change in kinetic energy (0) of the wheels due to frictional forces? Before coupling After coupling Select one: a. -68.10 b.136.20 C 68.10 O d.-136.20

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter8: Rotational Equilibrium And Dynamics

Section8.5: Rotational Kinetic Energy

Problem 8.4QQ: Two spheres, one hollow and one solid, are rotating with the same angular speed around an axis...

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